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

Let us write whether the following statements are true or false :

i. If then the least value of (sec² α + cos² α) is 2.

ii. The value of is 1.

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

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