﻿ The equation cos 2x + a sin x = 2a – 7 possesses a solution if : Kaysons Education

# The Equation Cos 2x + a sin x = 2a – 7 Possesses A Solution If

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## Question

### Solution

Correct option is

2 ≤ a ≤ 6

The given equation can be written as

1 – 2 sin2 x + a sin x = 2a – 7

⇒ 2sin2 x – a sin x + 2 a – 8 = 0

Hence, sin x = (a – 4)/2( the other value is not possible as . This value is possible only when

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