Question

pleaae answer this one​

Answer 1

Answer:

Answer in above picture

Step-by-step explanation:

Answer is cosA

Answer 2

Answer:

Using

cos3θ = 4cos³θ - 3cosθ

cos2θ = 2cos²θ - 1

$\frac{4 { \cos( \theta) }^{3} - 3\cos( \theta) }{2( { 2\cos( \theta) }^{2} - 1 )-1}$

4cos³θ - 3cosθ/4cos²θ - 2 -1

= 4cos³θ - 3cosθ/4cos²θ - 3

= cosθ(4cos²θ - 3)/ 4cos²θ -3

= cosθ