Question

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Answer 1

$15 - 8x^2 +x^4 sqrt[12]{x} = 15-8x^2+x^4*x^{ frac{1}{12} }= \ = 15-8x^2+x^{4+ frac{1}{12} } = 15-8x^2+x^{ frac{49}{12} } \ \ (15-8x^2+x^{ frac{49}{12} })'=0- 8*2*x^{2-1} +frac{49}{12} *x^{ frac{49}{12} -1} \ = -16x+ frac{49}{12} x^{ frac{37}{12} }= frac{49}{12} x^3 sqrt[12]{x}-16x$