The number of solutions of the equation (4–3)sinx–23cos2x=–41+3,x∈[–2π,5π2] is [2025]
(1)
Given, (4–3)sinx–23cos2x=–41+3, x∈[–2π,5π2]
⇒ (4–3)sinx–23(1–sin2x)=2(1–3)
⇒ 23sin2x+4sinx–3sinx–2=0
⇒ (2sinx–1)(3sinx+2)=0
⇒ sinx=12 [∵ sinx≠–23]
⇒ x=–11π6,–7π6,π6,5π6,13π6
∴ Number of solutions = 5.