What is the derivative of #y=3sin(x) - sin(3x)#?

2 Answers
Apr 9, 2018

#y=3sin(x)−sin(3x)#

#y'=3cosx−[cos(3x)*3]# #color(white)(ttttt# #["applying chain rule to" sin(3x)]#

#y'=3(cosx−cos3x)#

Apr 9, 2018

#dy/dx=3cosx-3cos3x#

Explanation:

#"differentiate "sin3x" using the "color(blue)"chain rule"#

#"Given "y=f(g(x))" then"#

#dy/dx=f'(g(x))xxg'(x)larrcolor(blue)"chain rule"#

#y=3sinx-sin3x#

#rArrdy/dx=3cosx-cos3x xxd/dx(3x)#

#color(white)(rArrdy/dx)=3cosx-3cos3x#