<p>This was in a Barron's prep book. It has to do with functions. </p>
<p>Solve x^5 -3x^3 +2x^2 - 3 > 0. </p>
<p><a href="-∞,%20-0.87">A</a>
<a href="-1.90,%20-0.87">B</a>
<a href="-1.90,%20-0.87">C</a> U (1.58, ∞)
<a href="-0.87,%201.58">D</a>
<a href="1.58,%20∞">E</a></p>
<p>I need some assistance understanding and solving this problem. Thanks in advance!</p>
<p>I believe you need a graphing calculator for this problem. Plug it into Y= in ur TI-83 (or 84 and 89) and graph it. First you find the zeros, which are -1.90, -.87, and 1.58.
You do this by doing 2nd TRACE and press 2 for zero.
Since the equation says it’s greater than zero, you gotta see where the graph is above the x-axis. That’s in between -1.90 and -.87 on the left side, 1.58 and infinity on the right side.
So yeah, I dont think you can do this without a graphing calculator.
EDIT: the answer’s C.</p>
<p>If you don’t use a graphing calculator, you can think of this function as starting with x^3 instead of x^5. When it is x^ odd power the graphs take on the same general shape. If you know what a x^3 function looks like, then you can deduce the correct answer using the process of elimination.</p>
<p>Or, if you don’t have a graphing calc, you can plot different points (maybe -1, -2, 0, 1, 2) into the equation to see which one gives you a value greater than 0. That takes some time but will also work.</p>
<p>Thanks for your assistance Krazy and xrCalico23!</p>