Question

If sin A + sin² A = 1, then the value of cos² A + cos⁴ A is

(a) 2

(b) 1

(c) −2

(d) 0

Answer 1

Here the given date is and

We have to find the value of

We know that the given relation is

……(1)

Now we are going to evaluate the value of

Here we are using the relation

This is same as the equation number (1)

Therefore

Hence the option (b) is correct.