dh/dx



x = 7 , h (x) = (x^-1/2 + 8x)(4 - x^-1)

It would be beneficial for you to write out your question. I assume you are trying to find the value of h' for x=7 of the function h()=(1/sqrtx + 8x)(4-1/x)

Do this as a product, uv
u= 1/sqrtx + 8x du= -/x^3/2 + 8
v= 4-1/x dv= 1/x^2

d uv/dx= udv/dx + v du/dx