help please.. find the length of the curve
o-o
let\[y=\frac{ x^4 }{ 16 } +\frac{ 1 }{ 2x^2 }\]
1 </ x </ 2
so far i have this \[\int\limits_{1}^{2}\sqrt{\frac{ 1 }{ 2 }+\frac{ x^6 }{ 16 }+x ^{-6}} dx\]
i simplified it which my derivative was \[\frac{ dy }{ dx }=\frac{ 1 }{ 4 }x^3-x ^{-3}\]
When you squared the y' you ended up with,\[\large\rm (y')^2\quad=\quad \frac{x^6}{16}\color{orangered}{-\frac12}+x^{-6}\]Right? And now you have a +1/2 in the middle instead of -1/2 when you add the 1. Remember this little trick?
uhhhh LOOl which trick D:
Your derivative squared gave you this,\[\large\rm \frac{x^6}{16}\color{orangered}{-\frac12}+x^{-6}\quad=\quad \left(\frac{x^3}{4}-x^{-3}\right)^2\]So then how bout this?\[\large\rm \frac{x^6}{16}\color{royalblue}{+\frac12}+x^{-6}\quad=\quad \]
like this D: |dw:1482211867285:dw|
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