Which is the completely factored form of 12x4 + 39x3 + 9x2? O 3x²(x - 3)(4x - 1)
O 3x²(x + 3)(4x + 1)
O 3x(x + 3)(4x + 1)
O 3x(x − 3)(4x + 1)

Show algebraically that f and g are inverse functions f(x)=x^2/-6; g(x)=square root of 2x+12

Two planes leave an airport at the same time, one flying east, the other flying west. the eastbound plane travels 20 mph slower. they are 1600 mi apart after 2 hr. find the speed of each plane.

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)