Question

If √[(1 - cosA)/2] = x, then the value of x is

Options:

1) cos(A/2)

2) tan(A/2)

3) sin(A/2)

4) cot(A/2)

Answer 1

root (1-CosA/2) = x

we know 1-CosA/2 = Sin^2A/2

Putting this value we get
root Sin^2A/2 = x
Thus
x = SinA/2

Thus the answer is option 3

Answer 2

Answer:

Option 3 is correct

$\sin (\frac{A}{2})$

Step-by-step explanation:

Given that:

$\sqrt{\frac{1-\cos A}{2}} = x$

Squaring both sides we get;

$\frac{1-\cos A}{2} = x^2$

We know that:

$\sin^2(\frac{A}{2}) = \frac{1-\cos A}{2}$

then;

$\sin^2(\frac{A}{2}) = x^2$

⇒$\sin (\frac{A}{2}) = x$

or

$x = \sin (\frac{A}{2})$

Therefore, the value of x is, $\sin (\frac{A}{2})$