Question

Find the maximum value of the expression 1/x + 5x + 10​

Answer 1

$= \frac{1}{x} + 5x + 10$

$= \frac{1}{x} + \frac{5x}{1} = 10$

$\frac{x + 5 { x }^{2} }{ x} = 10$

$5 {x}^{3} = 10x$

$5x(2 {x}^{2} ) = 2$

$2 {x}^{2} = 2$

${x}^{2} = \frac{2}{2}$

${x}^{2} = 1$

$x = \sqrt{2}$

$x = 2$