The value of  is

• 1

• -1

• 
• 

82.

If   then the value of  is:

• 
• 
• 
• 

If  where 0° < a < 90°, then the value of a is

• 0°

• 15°

• 45°

• 45°

Value of (cos 53° - sin 37°) is

• 0

• 1

• 2sin37°

• 2sin37°

If , then the value of  is

If sec (4x - 50°) = cosec (50° - x), then the value of x is

• 45°

• 90°

• 30°

• 30°

If  then the value of  is

• 
• 

• 3

• 3

If cos²x + cos⁴x = 1, then tan²x + tan⁴x = ?

• 0

• 1

• 2tan²x

• 2tan²x

If cos 27° = x, then value of 63° is

If θ is a positive acute angle and  then the value of θ is

• 60°

• 30°

• 45°

• 45°