Educational

If α + β = π/4, then the value of (1 + tan α)(1 + tan β) is (a) 1  (b) 2  (c) –2  (d) not defined

If α + β = π/4, Find the Value of (1 + tan α)(1 + tan β) If α + β = π/4, Find the Value of (1 + tan α)(1 + tan β) Question: If \[ \alpha+\beta=\frac{\pi}{4} \] then the value of \[ (1+\tan\alpha)(1+\tan\beta) \] is (a) \(1\) (b) \(2\) (c) \(-2\) (d) not […]

If α + β = π/4, then the value of (1 + tan α)(1 + tan β) is (a) 1  (b) 2  (c) –2  (d) not defined Read More »

If tan 69° + tan 66° – tan 69° tan 66° = 2k, then k = (a) –1  (b) 1/2  (c) –1/2  (d) none of these

If tan 69° + tan 66° − tan 69° tan 66° = 2k, Find k If tan 69° + tan 66° − tan 69° tan 66° = 2k, Find k Question: If \[ \tan69^\circ+\tan66^\circ-\tan69^\circ\tan66^\circ=2k \] then \[ k= \] (a) \(-1\) (b) \(\frac{1}{2}\) (c) \(-\frac{1}{2}\) (d) none of these Solution Using the identity: \[ \tan(A+B)

If tan 69° + tan 66° – tan 69° tan 66° = 2k, then k = (a) –1  (b) 1/2  (c) –1/2  (d) none of these Read More »

If cos (A – B) = 3/5 and tan A tan B = 2, then (a) cos A cos B = 1/5  (b) cos A cos B = –1/5 (c) sin A sin B = –1/5  (d) sin A sin B = –1/5

If cos(A − B) = 3/5 and tan A tan B = 2, Find cos A cos B and sin A sin B If cos(A − B) = 3/5 and tan A tan B = 2, Find cos A cos B and sin A sin B Question: If \[ \cos(A-B)=\frac{3}{5} \] and \[ \tan A\tan

If cos (A – B) = 3/5 and tan A tan B = 2, then (a) cos A cos B = 1/5  (b) cos A cos B = –1/5 (c) sin A sin B = –1/5  (d) sin A sin B = –1/5 Read More »

The maximum value of sin²(2π/3 + x) + sin²(2π/3 – x) is (a) 1/2  (b) 3/2  (c) 1/4  (d) 3/4

Find the Maximum Value of sin²(2π/3 + x) + sin²(2π/3 − x) Find the Maximum Value of sin²(2π/3 + x) + sin²(2π/3 − x) Question: The maximum value of \[ \sin^2\left(\frac{2\pi}{3}+x\right) + \sin^2\left(\frac{2\pi}{3}-x\right) \] is (a) \(\frac{1}{2}\) (b) \(\frac{3}{2}\) (c) \(\frac{1}{4}\) (d) \(\frac{3}{4}\) Solution Use the identity: \[ \sin^2\theta=\frac{1-\cos2\theta}{2} \] Therefore, \[ \sin^2\left(\frac{2\pi}{3}+x\right) = \frac{

The maximum value of sin²(2π/3 + x) + sin²(2π/3 – x) is (a) 1/2  (b) 3/2  (c) 1/4  (d) 3/4 Read More »

If A – B = π/4, then (1 + tan A)(1 – tan B) is equal to (a) 2  (b) 1  (c) 0  (d) 3

If A − B = π/4, Find (1 + tan A)(1 − tan B) If A − B = π/4, Find (1 + tan A)(1 − tan B) Question: If \[ A-B=\frac{\pi}{4} \] then \[ (1+\tan A)(1-\tan B) \] is equal to (a) \(2\) (b) \(1\) (c) \(0\) (d) \(3\) Solution Using the identity: \[

If A – B = π/4, then (1 + tan A)(1 – tan B) is equal to (a) 2  (b) 1  (c) 0  (d) 3 Read More »

If tan (A – B) = 1, sec (A + B) = 2/√3, then the smallest positive value of B is (a) 25π/24  (b) 19π/24  (c) 13π/24  (d) 11π/24

If tan(A − B) = 1 and sec(A + B) = 2/√3, Find the Smallest Positive Value of B If tan(A − B) = 1 and sec(A + B) = 2/√3, Find the Smallest Positive Value of B Question: If \[ \tan(A-B)=1 \] and \[ \sec(A+B)=\frac{2}{\sqrt3} \] then the smallest positive value of \[ B

If tan (A – B) = 1, sec (A + B) = 2/√3, then the smallest positive value of B is (a) 25π/24  (b) 19π/24  (c) 13π/24  (d) 11π/24 Read More »

If tan (π/4 + x) + tan (π/4 – x) = a, then tan²(π/4 + x) + tan²(π/4 – x) = (a) a² + 1  (b) a² + 2  (c) a² – 2  (d) none of these

If tan(π/4 + x) + tan(π/4 − x) = a, Find tan²(π/4 + x) + tan²(π/4 − x) If tan(π/4 + x) + tan(π/4 − x) = a, Find tan²(π/4 + x) + tan²(π/4 − x) Question: If \[ \tan\left(\frac{\pi}{4}+x\right) + \tan\left(\frac{\pi}{4}-x\right) =a \] then \[ \tan^2\left(\frac{\pi}{4}+x\right) + \tan^2\left(\frac{\pi}{4}-x\right) = \] (a) \(a^2+1\) (b) \(a^2+2\)

If tan (π/4 + x) + tan (π/4 – x) = a, then tan²(π/4 + x) + tan²(π/4 – x) = (a) a² + 1  (b) a² + 2  (c) a² – 2  (d) none of these Read More »

The value of cos (36° – A) cos (36° + A) + cos (54° + A) cos (54° – A) is (a) sin 2A  (b) cos 2A  (c) cos 3A  (d) sin 3A

Find the Value of cos(36° − A) cos(36° + A) + cos(54° + A) cos(54° − A) Find the Value of cos(36° − A) cos(36° + A) + cos(54° + A) cos(54° − A) Question: The value of \[ \cos(36^\circ-A)\cos(36^\circ+A) + \cos(54^\circ+A)\cos(54^\circ-A) \] is (a) \(\sin2A\) (b) \(\cos2A\) (c) \(\cos3A\) (d) \(\sin3A\) Solution Using the

The value of cos (36° – A) cos (36° + A) + cos (54° + A) cos (54° – A) is (a) sin 2A  (b) cos 2A  (c) cos 3A  (d) sin 3A Read More »

If tan θ = 1/2 and tan ϕ = 1/3, then the value of θ + ϕ is (a) π/6  (b) π  (c) 0  (d) π/4

If tan θ = 1/2 and tan ϕ = 1/3, Find the Value of θ + ϕ If tan θ = 1/2 and tan ϕ = 1/3, Find the Value of θ + ϕ Question: If \[ \tan\theta=\frac{1}{2} \] and \[ \tan\phi=\frac{1}{3} \] then the value of \[ \theta+\phi \] is (a) \(\frac{\pi}{6}\) (b) \(\pi\)

If tan θ = 1/2 and tan ϕ = 1/3, then the value of θ + ϕ is (a) π/6  (b) π  (c) 0  (d) π/4 Read More »

If sin (π cos x) = cos (π sin x), then sin 2x = (a) ±3/4  (b) ±4/3  (c) ±1/3  (d) none of these

If sin(π cos x) = cos(π sin x), Find sin 2x If sin(π cos x) = cos(π sin x), Find sin 2x Question: If \[ \sin(\pi\cos x)=\cos(\pi\sin x) \] then \[ \sin2x= \] (a) \(\pm\frac{3}{4}\) (b) \(\pm\frac{4}{3}\) (c) \(\pm\frac{1}{3}\) (d) none of these Solution Using the identity: \[ \cos\theta=\sin\left(\frac{\pi}{2}-\theta\right) \] Therefore, \[ \sin(\pi\cos x) =

If sin (π cos x) = cos (π sin x), then sin 2x = (a) ±3/4  (b) ±4/3  (c) ±1/3  (d) none of these Read More »