Question

If $\sin^{2}\theta = \frac{x^{2} + y^{2} + 1}{2x}$, then x must be

• A. – 3
• B. – 2
• C. 1
• D. None of these

Answer 1

Answer: (D)

None of these

Answer 2

$\sin^{2}\theta \leq 1$

∴$\frac{x^{2} + y^{2} + 1}{2x} \leq 1$ $x^{2} + y^{2} - 2x + 1 \leq 0$.

$(x - 1)^{2} + y^{2} \leq 0$

It is possible, iff $x = 1$ and $y = 0$,

i.e., It also depends on value of y.

Hence, option (4) is correct.