If sec 31° = x, then sin259° +
is equal to :
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. ![]()
Sec 31o = x
Sin (90o - θ) = Cosθ
Cosecθ = 1/Sinθ
Cosθ = 1/Secθ
Sin259o + 1/Sec231o - 1/Sin259oCosec259o
= Sin2(90 - 31)o + (1/Sec231o) - {1/(Sin259o × 1/Sin259o)
= Cos231o + (1/Sec231o) - 1
= (1/Sec231o) + (1/Sec231o) - 1
= (2/Sec231o) - 1
= (2/x2) - 1
= (2 - x2)/x2