Question

Find the limit as x approaches 0 of f(x)=(sin (3x) *cos(x))/4x

Answer 1

u can make limit (x->0) (sin (3x) *cos(x))/4x
= limit (x->0) (sin(3x)/4x) * limit (x->0) cos(x)
for limit (x->0) (sin(ax)/bx) = a/b and limit (x->0) cos(x) u just put x=0, so cos0=1

Answer 2

ok but what is the limit to the problem?

Answer 3

wait it would be zero wouldnt it

Answer 4

limit (x->0) (sin(ax)/bx) = a/b
so, limit (x->0) (sin(3x)/4x) = 3/4
this is abasic formula

Answer 5

ok