Question

The identity sin (theta/2) = +- sqrt 1-cos theta/2 is derived from which other identity?

Answer 1

Answer:

2nd option

Step-by-step explanation:

Using

sin²A = $\frac{1-cos2A}{2}$ ( take the square root of both sides )

sinA = ± $\sqrt{\frac{1-cos2A}{2} }$

Replace 2A with θ and A with $\frac{0}{2}$ , then

sin ($\frac{0}{2}$ ) = ± $\sqrt{\frac{1-cos20}{2} }$