Drag the tiles to the correct boxes to complete the pairs.
Match the expressions with their solution

a)    

b)

c)

d)

  cos 330° = 1- 2 sin² (165°)

Step-by-step explanation:

Step(i):-

By using trigonometry formulas

a)

cos2∝  = 2 cos² ∝-1

cos∝ = 2 cos² ∝/2 -1

1+ cos∝ =  2 cos² ∝/2

b)

cos2∝  = 1- 2 sin² ∝

cos∝  = 1- 2 sin² ∝/2

Step(i):-

Given

          we know that trigonometry formulas

         1- cos∝ =  2 sin² ∝/2

      Given

put ∝ = 315

     multiply with ' 2 sin (∝/2) both numerator and denominator

Apply formulas

  1- cos∝ =  2 sin² ∝/2

now we get

b)

               put ∝ = 330° above formula

c )

               put ∝ = 315° above formula

d)

     cos∝  = 1- 2 sin² ∝/2

   put      ∝ = 330°

      cos 330° = 1- 2 sin² (165°)