If y = cos x · cos 4x · cos 8x, then what is (1/y) (dy/dx) at x = π/4 equal to? - NDA Mathematics 2021 (II)

Two dice each numbered from 1 to 6 are thrown together. Let A and B…

An urn contains one black ball and one green ball. A second urn contains one…

What is the most probable number of successes in 10 trials with probability of success…

If y = cos x · cos 4x · cos 8x, then what is (1/y) (dy/dx) at x = π/4 equal to?