Math Insight

Gateway exam practice, version 8713

Math 1241, Fall 2020
Name:
Section:
Table/group #:
Total points: 10
Time limit: 50 minutes
  1. Consider the function $f(t)=10(0.5)^t. \;\;$ Find the half-life, i.e. find $t$ such that $f(t)=\frac{1}{2}f(0).$

    Half-life =

    (If you round your answer, include at least 4 significant digits.)

  2. Let $w(x) = x^{2} + 7$ and $u(x) = \sqrt{ 2 x}$. What is $w(u(x))$?

    $w(u(x)) = $

  3. Simplify the inequality below: \begin{align*} \left|\frac{7 x}{2} + 6\right|<9 \end{align*}


    $\lt x \lt$

  4. The difference between two positive numbers is 1 and the sum of their squares is 145.

    The numbers are

    Separate answers by a comma.

  5. Solve for U. \begin{align*} 6 = - 7 U \end{align*} $U = $

  6. Compute the value of $f(f(\frac{1}{ 2 }))$ for the function $f(x)=2x(1-x)$.

    $f(f(\frac{1}{ 2 })) =$

  7. Solve the equation $-4\left(y - 5\right)^{2} \left(y - 2\right) \left(y + 9\right)^{2} \left(9 y + 10\right) =0$.

    The solutions are $y = $

    If there are more than one solution, separate answers by commas

  8. Find the equation for the line through the points $(-1,1)$ and $(-4,-9)$.

    $y = $

  9. Let the variable $x$ be in the range \begin{align*} 2< x <7. \end{align*} If $y= 6 x + 2$, what is the range of the variable $y$?


    $\lt y \lt$

  10. Write the function $f(x)=9e^{ 6x+7 }$ in the form $f(x)=Ae^{kx}$.   What are the values of the parameters $A$ and $k$?

    $A=$
    , $k=$