Math Question

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1

<p>Hey guys! so I got this question correctly but I want to know how to answer it..</p>

<p>if x>0 and n is a nonnegative integer</p>

<p>2x^n+1 + x^n+2 = x^n+3 </p>

<p>which of the following must equal x^3?</p>

<p>A) 2+2x+x^2
B) 2x+x^2
C) 2+x^2
D) 2+x
E) 3x</p>

<p>so I just put n = 0 and I get B, but is there any other way to answer this question?</p>

2

<p>Divide every term by x^n. Because you know the rule of exponent, (x^a)/(x^b) = x^(a-b), we have 2x^(n+1-n) + x^(n+2-n) = x^(n+3-n), so n cancels and we get 2x + x^2 = x^3 -> B</p>

3

<p>wow! :S it is funny how I didn’t notice. thanks!</p>