SOLUTION: I need help! what does x to the power of minus 3 equal? and how do i work it out?!

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Question 739957: I need help! what does x to the power of minus 3 equal? and how do i work it out?!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The general rule is:
+a%5E%28-b%29+=+1+%2F+a%5Eb+
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Suppose you had +4%5E%28-2%29+
+4%5E%28-2%29+=+1+%2F+%284%5E2%29+ and
+1+%2F+%284%5E2%29+=+1+%2F+16+, so
+4%5E%28-2%29+=+1%2F16+
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Also, the negative exponents operate
just the positive exponents.
A general rule is:
+a%5E%28+b+%2B+c+%29+=+a%5Eb+%2A+a%5Ec+
Following this, suppose you had
+3%5E5+%2A+3%5E%28-3%29+
then
+3%5E5+%2A+3%5E%28-3%29+=+3%5E%28+5+-+3+%29+
+3%5E%28+5+-+3+%29+=+3%5E2+
+3%5E2+=+9+, so
+3%5E5+%2A+3%5E%28-3%29+=+9+
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Your problem is +x%5E%28-3%29+
Following the general rule,
+x%5E%28-3%29+=+1+%2F+%28x%5E3%29+
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hope this helps