Ans1) Let u= sinx, v= sin2x and w= sin3x
Using the formula, d(uvw)/dx= uv dw/dx+ vw du/dx+ wu dv/dx
= (sinx)(sin2x) d(sin3x) + (sin2x)(sin3x) d(sinx)/dx+ (sinx)(sin3x) d(sin2x)/dx
= (sinx)(sin2x)(3.cos3x) + (sin2x)(sin3x)(cosx) + (sinx)(sin3x)
Use the same formula for the second one
Ans 3) Let u= x^1/2, v= (2x+3)^1/2 and w= (x+5)^3
d(uv/w)/dx= [w. d(uv)dx- (uv)dw/dx] / w^2
