Use the Chain Rule to find dy/dx, for y = (u^4-9)^6 and u = 1 / x + 8. (Express numbers in exact form. Use symbolic notation and fractions where needed.)

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

How can (square root of 25) ^2 be rewritten?