Math Insight

Gateway exam practice, version 1180

Math 1241, Fall 2020
Name:
Section:
Table/group #:
Total points: 10
Time limit: 50 minutes
  1. Let the variable $x$ be in the range \begin{align*} 0< x <7. \end{align*} If $y= 7 x + 3$, what is the range of the variable $y$?


    $\lt y \lt$

  2. Simplify the inequality below: \begin{align*} \left|\frac{3 x}{5} + 1\right|<5 \end{align*}


    $\lt x \lt$

  3. Rewrite the exponential function \[ Q(t) = \frac{ 7 }{ 5^{t}4^{ t - 4 } } \] in the form $Q(t)=ab^t$, where we call $a$ the “initial value” (the value when $t=0$) and $b$ the “growth factor.” In this form:

    $a = $

    $b = $

  4. Consider the function $f(t)=13(0.4)^t. \;\;$ 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.)

  5. Let $w(x) = - 4 x^{2} + 2$ and $z(x) = \sqrt{ 7 x}$. What is $w(z(x))$?

    $w(z(x)) = $

  6. Solve for $q$. \begin{align*} - 6 q + 10 z = 6 q - 2 z - 4 \end{align*} $q = $

  7. Compute the value of $f(f(\frac{1}{ 4 }))$ for the function $f(x)=2x(1-x)$.

    $f(f(\frac{1}{ 4 })) =$

  8. Find the equation for the line through the point $(-10,9)$ with slope given by $m=- \frac{13}{7}$

    $y = $

  9. Factor the quadratic $z^{2} + 14 z + 45$.

    Answer =

  10. Solve the equation $9\left(y - 10\right) \left(y - 9\right)^{2} \left(y - 6\right)^{2} \left(7 y + 8\right) =0$.

    The solutions are $y = $

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