I tried to prepare before differentiation. Ergo;
Then I thought, that x^ax^b=a+b
(-1) + (-1) =-2; so x^-2, x by itself was equal to x^1 ergo, (-1)+(1)=0 so, x^0.
2x^-2; and 2x^0 (aka, 2x)
But answer is given as -2x^-3+2x
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Differentation help watch
- Thread Starter
- 16-05-2015 17:07
- 16-05-2015 17:16
So (x^-1 + x)^2 should expand to x^-2 + 2 + x^2
The two comes from multiplying x and x^-1 twice
dy/dx is then -2x^-3 + 2x
I'm not sure what you did wrong, it may have been a problem with your expansion?
Actually, I just realised what you did
x^0 is one, rather than x and you seem to have lost your x^2Last edited by pineneedles; 16-05-2015 at 17:22.