Chapter 5 Polynomials and Polynomial Functions - 5.9 Write Polynomial Functions and Models - 5.9 Exercises - Quiz for Lessons 5.7-5.9 - Page 399: 9

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Given: $f(x)=x(x-4)(x-1)(x+2)$ Find x-intercepts: $x-4=0 \rightarrow x=4\\x-1=0\rightarrow x=1\\x+2=0\rightarrow x=-2$ Let's find some points: $x=-1 \rightarrow y=-10\\x=3\rightarrow y=-30\\ x=5\rightarrow y=140$ $f(x) \rightarrow \infty$ as $x \rightarrow -\infty$ $f(x) \rightarrow \infty $ as $x \rightarrow \infty$