<p>Here's an SAT type problem.... I don't really understand how they do it.</p>
<p>What is 1/2x^(-1/2) + 1/2x^(-3/2) equal to?</p>
<p>The answer is (x+1)/(2x^(3/2))</p>
<p>I don't get it. I have a feeling it's something simple I'm not seeing. Please help. Thanks.</p>
<p>is it (1/2)x or (1)/(2x) ?</p>
<p>it's (1/2)x. Apparently this is a little hard...</p>
<p>Rewrite the negative exponents as fractions. You have 1/(2x^(1/2)) + 1/(2x^(3/2)). You need to have a common demoninator to add the fractions, so multiply the first fraction by x/x to get x/(2x^(3/2)) + 1/(2x^(3/2)). Then add the numerators and get the answer: (x + 1) / (2*x^(3/2))</p>
<p>First, please tell where you found it.</p>
<p>Factor (1/2)x^(-3/2) out:
1/2x^(-1/2) + 1/2x^(-3/2) =
(1/2)x^(-3/2) (x^(1) + 1) =
(1/2) (1/ x^(3/2)) (x + 1) =
(x + 1) 1/(2 x^(3/2)) =
(x + 1)/(2 x^(3/2))
Your intuition was telling you the truth.</p>
<p>I didn't see anything like that on the SAT :P</p>