In the figure, PQr is a semicircle while PQ and Qr are chords. QS is the perpendicular from Q to the diameter PR. What is the expression for QS?

The angle between latitudes 30oS and 13oN is

If x = 3 - √3 3 , find x2 + 36x2

If x = (all prime factors of 44) and y = (all prime factors of 60), the elements of X ∪ Y and X ∩ Y respectively are

What is the value of x satisfying the equation 42x43x 4 2 x 4 3 x = 2?

Evaluate logban if b = an

Simplify (1.25×10−4)×(2.0×10−1)(6.25×105)

Simplify 5√18 18 - 3√72 72 + 4√50

Find n if 34n = 100112