How do you find the derivative of #cos(pi*x^2)#?

1 Answer
Dec 16, 2016

Answer:

#-2pixsin(pix^2)#

Explanation:

differentiate using the #color(blue)"chain rule"#

#color(orange)"Reminder " color(red)(bar(ul(|color(white)(2/2)color(black)(d/dx(cos(f(x)))=-sin(f(x)).f'(x)))color(white)(2/2)|))#

#rArrd/dx[cos(pix^2)]=-sin(pix^2).d/dx(pix^2)#

#=-2pixsin(pix^2)#