The expression sin2 θ + cos2 θ - 1 = 0 is satisfied by how many values of θ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. Infinitely many values.
sin2θ + cos2θ - 1 = 0
⇒ 1 - 1 = 0
⇒ 0 = 0
This statement, 0 = 0, is always true. It doesn't depend on the specific value of θ.
Since sin θ and cos θ are defined for all real values of θ, the expression is satisfied by infinitely many values of θ.