All categories

2 years ago

Prove that:sin3A/sinA - cos3A/cosA=2

Mathematics

1 answer:

LekaFEV [45]2 years ago

6 0

The result essentially follows directly from the triple-angle identities,

sin(3A) = 3 sin(A) cos²(A) - sin³(A)

cos(3A) = cos³(A) - 3 sin²(A) cos(A)

Then

sin(3A)/sin(A) = 3 cos²(A) - sin²(A)

cos(3A)/cos(A) = cos²(A) - 3 sin²(A)

and

sin(3A)/sin(A) - cos(3A)/cos(A)

= 3(cos²(A) + sin²(A)) - (sin²(A) + cos²(A))

= 3 - 1

= 2

You might be interested in

SIMPLIFY THE EXPRESSION (m − 1)(-4)

anastassius [24]

Answer:

-4m + 4

Step-by-step explanation:

you distribute the -4 to the m making -4m and then distribute -4 to the -1 which makes +4

4 0

2 years ago

Write a rule in coordinate form for the translation from Triangle EFG to Triangle

DanielleElmas [232]

Answer:

1st option

Step-by-step explanation:

Consider the coordinates of F and F'

F (- 3, 4 ) and F' (- 1, 3 )

To go from - 3 → - 1 in the x- directions , means adding 2

To go from 4 → 3 in the y- direction means subtracting 1

Then translation rule is

(x, y ) → (x + 2, y - 1 )

7 0

2 years ago

Match the following differential equations with their solutions. The symbols A, B, C in the solutions stand for arbitrary consta

aleksley [76]

Answer:1

Step-by-step explanation:

4 0

2 years ago

Haley makes earrings and packages them into cube boxes that measure 1/6 foot wide. how many 1/6 foot cubic boxes can she fit int

navik [9.2K]

Answer: $28\ cubes$

Step-by-step explanation:

The volume of a cube can be found with this formula:

$V_{(c)}=s^3$

Where "s" is the lenght of any edge of the cube.

The formula for calculate the volume of a rectangular prism is:

$V_{rp}=lwh$

Where "l" is the lenght, "w" is the width and "h" is the height.

We need to find the volume of a cube box:

$V_1=s^3=(\frac{1}{6}ft)^3=\frac{1}{216}ft^3$

To find the volume of the shipping box, first we must convert the mixed number to an improper fraction:

$1\frac{1}{6}=\frac{(6*1)+1}{6}=\frac{7}{6}$

Then the volume of the shipping box is:

$V_2=lwh\\\\V_2=(\frac{7}{6}ft)(\frac{1}{3}ft)(\frac{1}{3}ft)=\frac{7}{54}ft^3$

Now, in order to find the number of cube boxes can Haley fits into a shipping box, you must divide the the volume of the shipping box by the volume of one cube. This is:

$\frac{\frac{7}{54}ft^3}{\frac{1}{216}ft^3}=28$

6 0

3 years ago

I don’t know the answer help! ?

Gelneren [198K]

Answer:

m∠8=120°

Step-by-step explanation:

Given that lines L and M are parallel to each other, keep in mind that ∠1 and ∠8 are opposite exterior angles, so they will be congruent to each other. Therefore, m∠8=120°.

7 0

2 years ago

Read 2 more answers

Prove that:sin3A/sinA - cos3A/cosA=2​

Prove that:sin3A/sinA - cos3A/cosA=2