The value of 

• 1

• 6

• 2

• 2

If x =  a sin θ - b cos θ,  y = a cos θ + b sin θ, then which of the following is true?

73.

The value of 
cot 41°. cot 42°. cot 43°. cot 44°. cot 45°. cot 46°. cot 47°. cot 48°. cot 49°.

• 1

• 0

• 

• 

If tan A = n tan B and sin A = m sin B, then the value of cos²A is

The value of the expression
(1 + sec 22° + cot 68°) (1 - cosec 22° + tan 68°) is

• 0

• 1

• -1

• -1

If  and  then the value of  equals

• 1

• 
• 
• 

If  then the value of   is:

If 

If  and  then the value of  is

• 1

• 2

• 3

• 3

The expression of
 is equal to