What would the derivative of c(x) = (10 - x) + 1.4*sqrt((x^2) + 25)

Answer 1

c(x) = (10 - x) + 1.4√(x^2 + 25)
dc/dx = -1 + 1.4(2x)/2√(x^2+25)
= 1.4x/√(x^2+25) - 1

because d/dx √u = 1/2√u du/dx