If sin A + sin B = 2 where and then let us find out the value of (cos A + cos B).

Let us fill in the blanks :

i. The value of is ________.

ii. If then the value of cos θ is __________

iii. If then the value of cos⁴θ – sin⁴θ is __________

If and then let us determine the values of both r and θ.

If 0° < θ < 90°, then let us calculate the least value of (9 tan² θ + 4 cot² θ).

Let us calculate the value of (sin² α + cos⁶ α + 3 sin² α cos² α).