SSC CGL 2023 PYQ — Question 67

SSC CGL - 14 July 2023 - Shift 3 • Quantitative Aptitude • Q67

If cos⁡βsecα\frac{cos ⁡β}{secα} = 15 and sin⁡βsec⁡α\frac{sin⁡β}{sec⁡α} = 16, then the value of sin2β is _________.

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1  i.e. 256481\frac{256}{481}.

Given that

If cos⁡βsecα\frac{cos ⁡β}{secα} = 15 and sin⁡βsec⁡α\frac{sin⁡β}{sec⁡α} = 16,

cos β = 15 sec α ......(1

sin β = 16 sec α .......(2

Equation 2 ÷ Equation 1

tan β = 16/15 = Perpendicular (P)/Base (B)

As we know,

Hypotanous (H) = √(P2 + B2)

⇒ H = √(162 + 152) = √(256 + 225) = √481

⇒ H2 = 481

Hence, the value of sin2β = P2/H2 = 256/481