#color(white)=d/dx(2cscx+5cosx)#
#=d/dx(2cscx)+d/dx(5cosx)#
#=2*d/dx(cscx)+5*d/dx(cosx)#
#=2*d/dx(cscx)+5*-sinx#
#=2*d/dx(cscx)-5sinx#
(I'm going to switch some terms around just so it's easier to look at.)
#color(white)=2*d/dx(cscx)-5sinx#
#=-5sinx+2*d/dx(cscx)#
#=-5sinx+2*d/dx(1/sinx)#
Quotient rule:
#=-5sinx+2*((d/dx(1)*sinx-1*d/dx(sinx))/(sinx)^2)#
#=-5sinx+2*((0*sinx-1*d/dx(sinx))/sin^2x)#
#=-5sinx+2*((0*sinx-1*cosx)/sin^2x)#
#=-5sinx+2*((-cosx)/sin^2x)#
#=-5sinx+2*(-cosx/sinx*1/sinx)#
#=-5sinx+2*(-cotx*cscx)#
#=-5sinx-2cotxcscx#
That's the answer. Hope this helped!