prove it please
answer only if you know​

Prove It Please Answer Only If You Know

Answers

Answer 1

Part (c)

We'll use this identity

[tex]\sin(x+y) = \sin(x)\cos(y) + \cos(x)\sin(y)\\\\[/tex]

to say

[tex]\sin(A+45) = \sin(A)\cos(45) + \cos(A)\sin(45)\\\\\sin(A+45) = \sin(A)\frac{\sqrt{2}}{2} + \cos(A)\frac{\sqrt{2}}{2}\\\\\sin(A+45) = \frac{\sqrt{2}}{2}(\sin(A)+\cos(A))\\\\[/tex]

Similarly,

[tex]\sin(A-45) = \sin(A + (-45))\\\\\sin(A-45) = \sin(A)\cos(-45) + \cos(A)\sin(-45)\\\\\sin(A-45) = \sin(A)\cos(45) - \cos(A)\sin(45)\\\\\sin(A-45) = \sin(A)\frac{\sqrt{2}}{2} - \cos(A)\frac{\sqrt{2}}{2}\\\\\sin(A-45) = \frac{\sqrt{2}}{2}(\sin(A)-\cos(A))\\\\[/tex]

-------------------------

The key takeaways here are that

[tex]\sin(A+45) = \frac{\sqrt{2}}{2}(\sin(A)+\cos(A))\\\\\sin(A-45) = \frac{\sqrt{2}}{2}(\sin(A)-\cos(A))\\\\[/tex]

Therefore,

[tex]2\sin(A+45)*\sin(A-45) = 2*\frac{\sqrt{2}}{2}(\sin(A)+\cos(A))*\frac{\sqrt{2}}{2}(\sin(A)-\cos(A))\\\\2\sin(A+45)*\sin(A-45) = 2*\left(\frac{\sqrt{2}}{2}\right)^2\left(\sin^2(A)-\cos^2(A)\right)\\\\2\sin(A+45)*\sin(A-45) = 2*\frac{2}{4}\left(\sin^2(A)-\cos^2(A)\right)\\\\2\sin(A+45)*\sin(A-45) = \sin^2(A)-\cos^2(A)\\\\[/tex]

The identity is confirmed.

==========================================================

Part (d)

[tex]\sin(x+y) = \sin(x)\cos(y) + \cos(x)\sin(y)\\\\\sin(45+A) = \sin(45)\cos(A) + \cos(45)\sin(A)\\\\\sin(45+A) = \frac{\sqrt{2}}{2}\cos(A) + \frac{\sqrt{2}}{2}\sin(A)\\\\\sin(45+A) = \frac{\sqrt{2}}{2}(\cos(A)+\sin(A))\\\\[/tex]

Similarly,

[tex]\sin(45-A) = \sin(45 + (-A))\\\\\sin(45-A) = \sin(45)\cos(-A) + \cos(45)\sin(-A)\\\\\sin(45-A) = \sin(45)\cos(A) - \cos(45)\sin(A)\\\\\sin(45-A) = \frac{\sqrt{2}}{2}\cos(A) - \frac{\sqrt{2}}{2}\sin(A)\\\\\sin(45-A) = \frac{\sqrt{2}}{2}(\cos(A)-\sin(A))\\\\[/tex]

-----------------

We'll square each equation

[tex]\sin(45+A) = \frac{\sqrt{2}}{2}(\cos(A)+\sin(A))\\\\\sin^2(45+A) = \left(\frac{\sqrt{2}}{2}(\cos(A)+\sin(A))\right)^2\\\\\sin^2(45+A) = \frac{1}{2}\left(\cos^2(A)+2\sin(A)\cos(A)+\sin^2(A)\right)\\\\\sin^2(45+A) = \frac{1}{2}\cos^2(A)+\frac{1}{2}*2\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\\sin^2(45+A) = \frac{1}{2}\cos^2(A)+\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\[/tex]

and

[tex]\sin(45-A) = \frac{\sqrt{2}}{2}(\cos(A)-\sin(A))\\\\\sin^2(45-A) = \left(\frac{\sqrt{2}}{2}(\cos(A)-\sin(A))\right)^2\\\\\sin^2(45-A) = \frac{1}{2}\left(\cos^2(A)-2\sin(A)\cos(A)+\sin^2(A)\right)\\\\\sin^2(45-A) = \frac{1}{2}\cos^2(A)-\frac{1}{2}*2\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\\sin^2(45-A) = \frac{1}{2}\cos^2(A)-\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\[/tex]

--------------------

Let's compare the results we got.

[tex]\sin^2(45+A) = \frac{1}{2}\cos^2(A)+\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\\sin^2(45-A) = \frac{1}{2}\cos^2(A)-\sin(A)\cos(A)+\frac{1}{2}\sin^2(A)\right)\\\\[/tex]

Now if we add the terms straight down, we end up with [tex]\sin^2(45+A)+\sin^2(45-A)[/tex] on the left side

As for the right side, the sin(A)cos(A) terms cancel out since they add to 0.

Also note how [tex]\frac{1}{2}\cos^2(A)+\frac{1}{2}\cos^2(A) = \cos^2(A)[/tex] and similarly for the sin^2 terms as well.

The right hand side becomes [tex]\cos^2(A)+\sin^2(A)[/tex] but that's always equal to 1 (pythagorean trig identity)

This confirms that [tex]\sin^2(45+A)+\sin^2(45-A) = 1[/tex] is an identity


Related Questions

HOW DO YOU FIND ANGLE 1

Answers

Answer:

If we add up all the angles of any triangle, we should get 180 degrees. Therefore, Angle C = 90 (angle A) - 45 (angle B) = 45 degrees. Since there was a ray drawn from A through C the exterior angle of angle C is angle 1.

Step-by-step explanation:

a "one angle" A degree (in full, a degree of arc, arc degree, or arcdegree), usually denoted by ° (the degree symbol), is a measurement of a plane angle in which one full rotation is 360 degrees. ... Because a full rotation equals 2π radians, one degree is equivalent to π180 radians.

If we add up all the angles of any triangle, we should get 180 degrees. Therefore, Angle C = 90 (angle A) - 45 (angle B) = 45 degrees. Since there was a ray drawn from A through C the exterior angle of angle C is angle 1.

Work out the volume of this cylinder,
Give your answer rounded to 1 DP.
5cm
14cm

Answers

Answer:

Ykjhcgighgy7vgygoohgvg

Answer:

1,099.6

Step-by-step explanation:

if the radius is 5 and height is 14

you do

V=(pi)r squared × height

Part 1
Horatio installed new machinery at his machining company. Now it takes only minute to manufacture each part and 4 minutes to pack all the
parts for an order. Write an expression that shows how many minutes it takes to complete an order, assuming there are x parts in an order,

Answers

Answer:

1/2 x +4

Step-by-step explanation:

Sorry I was late! But I hope this helps! (this is correct on edmentum I don't know about anything else though)

I’m sooo confused rn please help pleaseeeeeee

Answers

Answer:

i believe the answer is c

Step-by-step explanation:

i'm not entirely sure but i hope this helps :)

have a nice day !!

**please let me know if this was wrong**

 

Answer:

B & C

Step-by-step explanation:

you have to solve for x in both a negative and positive way

PLEASE HELP!!!!! (PICTURE BELOW!!)

Answers

Draw a right triangle. The Pythagorean theorem is a^2 + b^2 = c^2
Your answer would be with the variable c
3^2 + 4^2 = c^2
9 + 16 = c^2
c^2 = 25
c = 5
Your welcome! :)

A dolphin jumps out of the water with an initial velocity of 20 feet per
second (assume its starting height is O feet). Use the vertical motion
model, h = - 16t2 + vt +8, where v is the initial velocity in feet per
second and s is the height in feet, to calculate the amount of time the
dolphin is in the air before it hits the water again. Round your answer
to the nearest tenth if necessary.
Time in air: seconds

Answers

Answer:

1.6 Seconds

Step-by-step explanation:

The equation would be h(t)=-16t^2+20t+8 since 20 is the velocity, and once you input that onto a graph the answer of when it hits the ground is 1.569 seconds, so rounded is 1.6 seconds.

What is the length of CF?

Answers

Answer:

8.5

Step-by-step explanation:

BF * EF = CF * DF

7 * 17 = CF * 14

119 = CF * 14

CF = 119 / 14

CF = 8.5

I think answer is 8.5

Jackson wants to make at least $150 this weekend so that he can buy some new
baseball cleats. If he earned $77.50 on Saturday, write an inequality to find the amount
of cash he must make on Sunday.

Answers

Answer:

m ≥ $72.50

Step-by-step explanation:

Can you simply these fractions?

Answers

Answer:

Yes you can.

Step-by-step explanation:

2/14= 1/7

3/15= 1/5

25/35= 5/7

20/24= 10/12= 5/6

6/18= 3/9= 1/3

8/20= 4/10= 2/5

10/15= 2/3

6/14= 3/7

4/40= 1/10

20/35= 4/7

find the area of a square of side 7.2 cm​

Answers

Answer:

51.84 cm²

Step-by-step explanation:

in a square

lengths (L) = 7.2 cm

Area of square

= L²

= ( 7.2 cm) ²

= 51.84 cm²

Hope it will help :)

White Kittens
Gray Kittens
Male
3
2.
Female
5
5
Find the ratio of white male and gray male kittens to white female and gray female kittens.
O 3: 2:5:5
O 5:7
05:10
03:5
2 3 4
02
5
5
7
8
9
1
https://weskids.schoology.com/common-assessment-delivery/start/4718034729?action=onresume&submissionid=4319101503
Type here to search
SI

Answers

Answer:

im pretty sure its 5:10

there are 5 male cats and 10 female cats

Step-by-step explanation:

If you deposit $24,500 into a bank account paying 6% annual interest compounded
semi-annually for 5 years, how much interest will you earn? Round to the nearest cent.

Answers

Answer:

$7,719.33

Step-by-step explanation:

$24,500 x 0.06 = $1,470

($24,500 + $1,470) x 0.06 = $1,558.20

($24,500 + $1,558.20) x 0.06 = $1,563.49

($24,500 + $1,563.49) x 0.06 = $1,563.81

($24,500 + $1,563.81) x 0.06 = $1,563.83

$1,470 + $1,558.20 + $1,563.49 + $1,563.81 + $1,563.83 = $7,719.33

(Need Help Quickly) find the measurement indicated in each trapezoid. (ISOSCELES TRAP) Do NOT include units (degrees, inches, feet, etc).*

Answers

Answer:

Notice in my attached drawing that I have located point H in two different locations, point H and point H2 for argument purposes.

Line FE is equal to line GH in length.

angle at corner F is 95 degrees.

The angle at point E varies with the location of point H, or with the length of line FG.

More information is needed to determine an exact angle at point E.

Find the area of a circle with radius,
r
= 40cm.
Give your answer rounded to 3 SF.

Answers

Answer:

hiiiiiiiiiiiiiiiiiiiiiiii

Explain 3 areas in everyday life when you use math.

Answers

If u become a teacher , to get into collage and uni
Managing money,understanding sports and baking/cooking

Please and Thank You ​

Answers

Answer:

I believe it is D, 5.

Step-by-step explanation:

Plsss help want is the second answer

Answers

Answer:

5 1/2 is your second answer :)

Answer:

[tex]A)5\frac{1}{2}[/tex]

Step-by-step explanation:

To multiply a number and a mixed number, first convert the improper fraction to a mixed number. This can be done by multiplying the "number" part of the mixed number by the denominator (number underneath the fraction bar) and then adding the result to the numerator. After doing so, one can either multiply the improper fraction by the number, and then simplify the result, or one can cross simplify the number and the denominator, then multiply by the numerator.

[tex]4 * 1\frac{3}{8}\\\\4 * \frac{11}{8}\\\\=\frac{44}{8}\\\\= \frac{11}{2}[/tex]

Now one must convert this improper fraction to a mixed number. One can do this by diving the numerator by the denominator, writing the result as the "number" part of the mixed number, and then writing the remainder as the numerator of the fraction.

[tex]5\frac{1}{2}[/tex]

Periodic Functions Determine the period. 10 0 Enter​

Answers

Answer:

no

Step-by-step explanation:

Jo has an appointment at 3pm. She has to travel 21 miles and will drive at an average speed of 30 mph. To arrive exactly on time, what time should she leave? Give your answer as a time on the 24-hour clock

Answers

2:18pm

21/30*60=42min trip

Help Asap i need my work done fast

Answers

Answer:

2. 4

3. 15

4. integer zero

What is an equation of the line that passes through the points (-4, -2) and
(-8, 3)?

Answers

Answer:

[tex]y=\frac{-5}{4}x-7[/tex]

Step-by-step explanation:

The equation of the line would be

Y= - 5/4x-7

Hope this helps

Have a great day/night

Feel free to ask any questions

Measures of dispersion are used in finance as a proxy for risks. explain​

Answers

Answer:

Kindly check explanation

Step-by-step explanation:

Measures of dispersion are used to determine the variability of data points of samples ; it measures how much a given data deviates or behaves about the mean value or point. Measures of dispersion or variability include standard deviation and variance.

In finance, data with high degree of vatibalitu are considered as being unstable because this shows a high level of uncertainty about the average confidence of the output for such investment or business. Hence. Highly variable investments are cindisderdd volatile and risky

The 6th grade class is going on a Field Trip. The Adult to Student ratio is 2:5. If there are a total of 70 people on the Field trip, how many adults are on the field trip?
Plz Help plz

Answers

Answer:I think it 20 adult to 50 kids

Step-by-step explanation:

After the math contest, Basil noticed that there were four extra-
large pizzas that were left untouched. In addition, another three
slices of pizza were uneaten. If there were a total of 51 slices of
pizza left, how many slices does an extra-large pizza have?
MATH
CONTEST
3:30
RM
105
EX PIZZA
EX.16. DIZZA
XG. PIZZA
X LG PIZZA
14
12.
15

Answers

Answer:

correct answer = 12

Step-by-step explanation:

the extra large pizza contains = 12 slices of pizza.

plz mark my answer as brainlist plzzzz.

hope this will be helpful to you ☺️

Answer:

An extra large pizza has 12 slices

Slope Please help!!!!!

Answers

Answer:

2/3

Step-by-step explanation:

2/3

Step-by-step explanation:

Very Simple

Take 2 points

x,y

x1,y1= 3,2

x2,y2=6,4

Find the slope

Y2-Y1/X2-X1

4-2/6-3

2/3

f(x)=x+2
g(x)=3x^2-5

Find (f•g)(x).

Answers

Answer:

f (  [tex]x^{2}[/tex]+ 5 ) = 3[tex]x^{2}[/tex] + 13

Step-by-step explanation:

Posting for a freind please hurry

Answers

Answer:

2) 16.2

3)18.2

4)16.6

Step-by-step explanation:

Answer:

3. 18.6.

4. 17.2.

Step-by-step explanation:

there you go calculators are fun

Simplify the expression 10a + 5b + 3 - 25a + 2b - 18 + 3b - 5a pls!!!

Answers

Answer:

−20a + 10b − 15

Step-by-step explanation:

The expression simplified is: −20a + 10b − 15

hope this helps

Find the area of the sector.
290 degrees
9ft radius

Answers

Answer:

area if sector =290/360 ×πr²=290/360 ×π×9²

=205.07=205 ft²

Answer:

Step-by-step explanation:

9ft= 274.32cm

(290/360)xπ×274.32²

=190440.9389 cm²

then round this to however many decimal places you need

Find the measure of the angle indicated in bold.
14)
А) 120
C) 115°
B) 100P
D) 140°

Answers

Answer:

115 sirrrrr

Step-by-step explanation:

Other Questions
According to the lyrics, what were some of the issues of the 1800 presidential election? The point (2, 20) lies on the graph of y = kx'. Write the value of k. 5. It makes me sick to think how long it took to make changes. Recently,America's dietary establishment has been changing its tune and suggesting that fatsare okay to consume. Finally!logic , authority , emotion Explain the impact of planes and pulleys on work and force. Select the facts that are accurate.o planes and pulleys can decrease the level of force required to move an objectO planes and pulleys can decrease the level of work to move an objecto planes and pulleys can increase the speed of completed worko planes and pulleys can change the direction of applied force Which two quantities are in a proportional relationship, and why? Dobla__A la derecho CuadraHasta Desde How did Dollar Diplomacy help prevent costly wars? help me help........... arcsin0=? arccos0=? arctan1=? What is the central argument or point of the piece Cellular respiration is similar in both plants and animals in what way? find the circumference of the circle shown below. Remember to use 3.14 for LaTeX: \pi, and be sure to round your final answer to the nearest hundredth, as needed. find the inequality represented by the graph pleasseee help me What organ systems are involved when running? What is the use of by products of sugar industry 1. Joe worked 80 hours in the last pay period (2 weeks) and he earns $12 perhour. Find the area for 5 and 7 two hundred seventy-three divided by twenty-four Leading is more important for the highest-level manager than planning I need help with this look at picture Complementary angles