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jmc

algebra intermediate

Problem

Find all real values of which satisfy
Solution
Let We make a sign table for each of the three factors on the left-hand side: \begin{array}{c|ccc|c} &$t$ &$2t-3$ &$4t-2$ &$f(t)$ \\ \hline$t<0$ &$-%%DISP_0%%amp;$-%%DISP_0%%amp;$-%%DISP_0%%amp;$-$\\ [.1cm]$0<t<\frac{1}{2}$ &$+%%DISP_0%%amp;$-%%DISP_0%%amp;$-%%DISP_0%%amp;$+$\\ [.1cm]$\frac{1}{2}<t<\frac{3}{2}$ &$+%%DISP_0%%amp;$-%%DISP_0%%amp;$+%%DISP_0%%amp;$-$\\ [.1cm]$t>\frac{3}{2}$ &$+%%DISP_0%%amp;$+%%DISP_0%%amp;$+%%DISP_0%%amp;$+$\\ [.1cm]\end{array}Therefore, we have when or Because the inequality is non-strict, we must also include the values of for which which are and Putting all this together, we get that the set of solutions for is
Final answer
(-\infty, 0] \cup (\tfrac12, \tfrac32]