The value of sin² θ + cos² θ is same as the value of which of the following?

Calculations:

The value of sin2 θ + cos2 θ is a well known trigonometric identity which is always equal to 1, regardless of the value of θ.

So the correct answer will be the option that also equals 1.

sin2 θ ⋅ cos2 θ ≠ 1
cosec2 θ - cot2 θ = 1 by the Pythagorean identity because cosec2 θ - cot2 θ = 1
sec2 θ + tan2 θ ≠  1 but equals another Pythagorean identity sec²θ  = 1 - tan²θ

 \(\frac{1}{\sin ^2 \theta}+\frac{1}{\cos ^2 \theta}\) ≠ 1.

Hence, The Correct Answer is option 2.