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Calcus help

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Can someone tell me how to work out part C please
Reply 1
Original post by Msjaygaab
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Can someone tell me how to work out part C please


You've found dy/dx, haven't you? Equate it to zero and solve for x, then plug it back into the equation of the curve to find the corresponding y.
Reply 2
Yeah I got 1-32x^-5=0
How do I solve that for X?
Reply 3
Original post by Msjaygaab
Yeah I got 1-32x^-5=0
How do I solve that for X?


Assuming that that's correct:

132x5=032x5=1x5=132    x5=125    x5=(12)5    \displaystyle 1 - 32x^{-5} = 0 \Rightarrow 32x^{5} = 1 \Rightarrow x^5 = \frac{1}{32} \iff x^5 = \frac{1}{2^{5}} \iff x^5 = \left(\frac{1}{2}\right)^5 \iff \cdots
Original post by Msjaygaab
Yeah I got 1-32x^-5=0
How do I solve that for X?


recall that xn=1xnx^{-n}=\dfrac{1}{x^n} and get one term on each side of the equation.
Stationary/minimum/maximum points occur when the derivative equals zero because imagine drawing a tangent at the minimum point- the gradient is 0 because it's a horizontal line.
Reply 6
is there any room for me?

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