Chapter 8 – Introduction to Trignometry

If cos (α + \(\beta\)) = 0, then sin (α – \(\beta\)) can be reduced to

If cos (40° + A) = sin 30°, the value of A is:?

If sin x + cosec x = 2, then sin19x + cosec20x =

If cos 9a = sin a and 9a < 90°, then the value of tan 5a is

7 sin2θ + 3 cos2θ = 4 then :

(1 + tanθ + secθ) (1 + cotθ – cosecθ) is equal to

Ratios of sides of a right triangle with respect to its acute angles are known as

If tan θ = \(\frac { 12 }{ 5 }\), then \(\frac { 1+sinθ }{ 1-sinθ }\) is equal to

The value of cos θ cos(90° – θ) – sin θ sin (90° – θ) is:

If x = a cos θ and y = b sin θ, then b2x2 + a2y2 =

If ΔABC is right angled at C, then the value of cos (A + B) is

If x and y are complementary angles, then

sin (45° + θ) – cos (45° – θ) is equal to

If 0° < θ < 90°, then sec 0 is

In right triangle ABC, right angled at C, if tan A = 1, then the value of 2 sin A cos A is

Given that sin A=\(\frac { 1 }{ 2 }\) and cos B=\(\frac { 1 }{ \sqrt { 2 } }\) then the value of (A + B) is:

If sin A = \(\frac { 1 }{ 2 }\), then the value of cot A is

If \sqrt{3tanθ = 3sinθ, then the value of sin2θ−cos2θ is

Out of the following options, the two angles that are together classified as complementary angles are

If sin θ − cos θ = 0, vthen the value of θ is

If tan 2A = cot (A – 18°), then the value of A is

If cos A + cos2 A = 1, then sin2 A + sin4 A is

If sin θ + sin2 θ = 1, then cos2 θ + cos4 θ = ____

sin 2B = 2 sin B is true when B is equal to

25. The value of cos 0°. cos 1°. cos 2°. cos 3°… cos 89° cos 90° is

26. If x tan 45° sin 30° = cos 30° tan 30°, then x is equal to

27. If x and y are complementary angles, then

28. sin 2B = 2 sin B is true when B is equal to

29. If A, B and C are interior angles of a ΔABC then cos(B+C2) is equal to