Question 195224
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In a word, no.  Prove it to yourself.  Construct the binomial *[tex \LARGE (w - a)] where *[tex \LARGE a] is the root you calculated.  Then square the binomial.  If the result is different than *[tex \LARGE w^2 + 225] then you can be assured there is another root.


The Fundamental Theorem of Algebra says that a polynomial of degree <i>n</i> has exactly <i>n</i> factors of the form (<i>x</i> - <i>a</i>). Each factor represents a root of the equation.  The only way to have a single root for a quadratic is for the polynomial to be a perfect square -- and the only perfect square quadratic polynomials in a single variable are trinomials.


Where you went wrong is that when you took the square root of both sides of your equation, you forgot to consider both the positive and negative roots.  Remember that if *[tex \LARGE x^2 = 4] then *[tex \LARGE x = 2] or *[tex \LARGE x = -2].


The roots of your equation are *[tex \LARGE w = \pm 15i].


Now, if you multiply *[tex \LARGE (w - 15i)(w + 15i)] you will get *[tex \LARGE w^2 + 225]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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