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elizbaker45
help.... A stone is thrown vertically upwards from the edge of a cliff on mars (where the acceleration of gravity is 12ft/s^2) with an initial velocity of 64 ft/s from a heigh of 192 feet above ground. The height of the stone above ground after t seconds iss given by h(t)=-6t^2+64t+192 a. when does the stone reach its highest point? What is the highest point? B. when does the stone hit the ground? What is it's velocity when it hits the ground?
i'm in the class now. thats the problem
take the derivative, set it equal to zero, solve for t (btw, the derivative will be a function that gives you the velocity as a function of t, which is relevant for part (b)) for b, set the height h(t)= 0 and solve for t.