40. A punter kicked a football with an initial velocity of 84 feet per second. The height (in feet) of the ball, \( h \), at fime \( r \) seconds is given by the function \( h(t)=-16 R+84 t+2 \) If the ball is caught by another player down the field at a height of 4 feet, how long was the ball was in the air?

Complete the square to write \( y=2 x^{2}+12 x-7 \) in graphing form. Then determine the vertex and the intercepts of the parabola. 1

15 It is given that \( t=\frac{b^{2}-4}{3-b^{2}} \). Express \( b \) in terms of \( t \)

Câu 03: (a) Rût gơn biểu thực \[ \left(\frac{1-x}{x^{2}+x^{3}-x^{4}}-\frac{x^{2}+x+2}{x^{5}-x^{3}-2 x^{2}-x}\right):\left(\frac{1+x^{4}}{x^{3}+x^{4}+x^{5}}-\frac{1-x+x^{2}}{x}\right) \] (b) Phân tích phân thức \( \frac{1}{(x-1)(x-2)(x-3)(x-4)} \) thành tổng các phân thức dơn giản.

\( f(x)=5 x+6 ; g(x)=3 x-2 \) (h) Find \( \left(\left.\bar{g}\right|^{(1)}\right. \) \( \left(\frac{f}{g}\right)(1)=\square \) (Type an integer or a simplified fraction.)

Simplify he following fully: \( \frac{3^{3+1}-3^{-1}}{23^{x}} \) \( \frac{3^{x} \cdot 3^{1}-3^{x} \cdot 3^{-1}}{2 \cdot 3^{x}} \frac{3^{x}\left(1-\frac{1}{3}\right)}{23^{x}} \)