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Need help with this polynomial?
3x^4+5x^3-2x^2
Okay, this is part of my study material for my precalc midterm tomorrow.
Basically, what my professor is asking is to find all possible rational zeroes, find all real zeroes, find the x intercept, find the y intercept, and find the end behavior.
What I understand so far is the y intercept (hur duhhr), and the end behavior, but I feel totally lost in all the other aspects. The only tool I know of to find possible zeroes is the rational roots tests, but how the $%# does that work when the constant coefficient is essentially zero? Also, how do I factor? I know if the polynomial is ^3 leading term, I can use one of the zeroes with synthetic division to reduce the equation to a quadratic and factor out the other zeroes from there, but this just leaves me confused.
2 個解答
- 匿名9 年前最愛解答
Just factor out x^2 (so two roots at x = 0) ... then it will make sense.
- Math_Astro_ManLv 49 年前
Like OzoneGuy said, factor out x^2 term
x^2(3x^2 + 5x - 2) = 0
Use the quadratic formula for the second factor and then you will get your roots.
The x^2 term implies that the graph crosses through the origin, meaning the origin is a root.
