JEE Main 2025 4 April Morning Shift
Exam JEE Main
Year 2025
Date 4 April
Shift Morning Shift
Subject Mathematics
Chapter Trigonometric Equations
JEE Main 2025 · 4 April · Morning Shift · Mathematics · Trigonometric Equations
If 10 ^4 θ+15 ^4 θ=6 , then the value of 27 cosec^6 θ+8 ^6 θ 16 ^8...
If
10 sin 4 θ + 15 cos 4 θ = 6 10 \sin ^4 \theta+15 \cos ^4 \theta=6 10 sin 4 θ + 15 cos 4 θ = 6 , then the value of
27 cosec 6 θ + 8 sec 6 θ 16 sec 8 θ \frac{27 \operatorname{cosec}^6 \theta+8 \sec ^6 \theta}{16 \sec ^8 \theta} 16 s e c 8 θ 27 cosec 6 θ + 8 s e c 6 θ is:
Options A 2 5 \frac{2}{5} 5 2 B 3 4 \frac{3}{4} 4 3 C 3 5 \frac{3}{5} 5 3 D 1 5 \frac{1}{5} 5 1
Correct answer A. 2 5 \frac{2}{5} 5 2
Step-by-step solution
10 ( sin 2 θ ) 2 + 15 ( 1 − sin 2 θ ) 2 = 6 Let sin 2 θ = t ⇒ 10 t 2 + 15 ( 1 − t ) 2 = 16 10 t 2 + 15 − 30 t + 15 t 2 = 6 25 t 2 − 30 t + 9 = 0 ( 5 t − 3 ) 2 = 0 sin 2 θ = 3 5 and cos 2 θ = 2 5 27 × 125 27 + 8 + 125 8 16 ( 5 2 ) 4 = 250 125 × 5 = 2 5 \begin{aligned} & 10\left(\sin ^2 \theta\right)^2+15\left(1-\sin ^2 \theta\right)^2=6 \\ & \text{ Let } \sin ^2 \theta=\mathrm{t} \Rightarrow 10 \mathrm{t}^2+15(1-\mathrm{t})^2=16 \\ & 10 \mathrm{t}^2+15-30 \mathrm{t}+15 \mathrm{t}^2=6 \\ & 25 \mathrm{t}^2-30 \mathrm{t}+9=0 \\ & (5 \mathrm{t}-3)^2=0 \\ & \sin ^2 \theta=\frac{3}{5} \text{\text{ and } } \cos ^2 \theta=\frac{2}{5} \\ & \frac{27 \times \frac{125}{27}+8+\frac{125}{8}}{16\left(\frac{5}{2}\right)^4}=\frac{250}{125 \times 5}=\frac{2}{5}\end{aligned} 10 ( sin 2 θ ) 2 + 15 ( 1 − sin 2 θ ) 2 = 6 Let sin 2 θ = t ⇒ 10 t 2 + 15 ( 1 − t ) 2 = 16 10 t 2 + 15 − 30 t + 15 t 2 = 6 25 t 2 − 30 t + 9 = 0 ( 5 t − 3 ) 2 = 0 sin 2 θ = 5 3 and cos 2 θ = 5 2 16 ( 2 5 ) 4 27 × 27 125 + 8 + 8 125 = 125 × 5 250 = 5 2
Practice Trigonometric Equations on Quantrex Academy →
← Previous question If for θ ∈[-(π)/(3), 0] , the points (x, y)=(3 (θ+(π)/(3)), 2 (θ+(π)/(6))) lie on x y+α…Next question → The number of solutions of equation (4- 3 ) x -2 3 ^2 x=- 4 1+ 3 , x ∈[-2 π, (5 π)/(2)] is
More from Trigonometric Equations
Match each entry in List-I to the correct entry in List-II and choose the correct option.… JEE Advanced 2026 Passage: Consider the curve C_1 given by y = e^ -x for x ∈ [0, 10π] , and the curve C_2… JEE Advanced 2026 Let S = \ θ ∈ (-2π, 2π) : θ + 1 = 3 θ\ . Then ∑_ θ ∈ S θ is equal to: JEE Main 2026 If S = \ θ ∈ [-π, π] : θ (5θ)/(2) = 7θ (7θ)/(2)\ , then n(S) is equal to _______. JEE Main 2026 Let S = \ x ∈ [-π, π] : x ( x + x) = a, a ∈ ℤ\ . Then n(S) is equal to : JEE Main 2026 The number of elements in the set \ x ∈[0,180^ ∘ ]: (x+100^ ∘ )= (x+50^ ∘ ) x (x-50^ ∘ )\… JEE Main 2026 Number of solutions of 3 2 θ+8 θ+3 3 =0, θ ∈[-3 π, 2 π] is: JEE Main 2026 The number of solutions of the equation 2 θ (θ)/(2)+ (5 θ)/(2)=2 ^3 (5 θ)/(2) in… JEE Main 2025 If for θ ∈[-(π)/(3), 0] , the points (x, y)=(3 (θ+(π)/(3)), 2 (θ+(π)/(6))) lie on x y+α… JEE Main 2025 The number of solutions of equation (4- 3 ) x -2 3 ^2 x=- 4 1+ 3 , x ∈[-2 π, (5 π)/(2)] is JEE Main 2025 The number of solutions of the equation 2 x+3 x=π, x ∈[-2 π, 2 π]-\ ± (π)/(2), ± (3… JEE Main 2025 If θ ∈[-(7 π)/(6), (4 π)/(3)] , then the number of solutions of 3 cosec^2 θ-2( 3 -1)… JEE Main 2025 If θ ∈[-2 π, 2 π] , then the number of solutions of 2 2 ^2 θ+(2- 6 ) θ- 3 =0 , is equal… JEE Main 2025 The sum of all values of θ ∈[0,2 π] satisfying 2 ^2 θ= 2 θ and 2 ^2 θ=3 θ is JEE Main 2025 Let f: ℝ arrow ℝ be a function defined by f(x)=\ array cc x^2 ((π)/(x^2)), & if x ≠ 0 0… JEE Advanced 2024 Let (π)/(2) < x < π be such that x= -5 11 . Then ( (11 x)/(2))( 6 x- 6 x)+( (11 x)/(2))(… JEE Advanced 2024
Full Trigonometric Equations list
Trigonometric Equations JEE Maths PYQs JEE Mathematics PYQs
All JEE Main PYQs