Question #f1b4f

3 Answers
Jul 22, 2017

#lim_(x->0) sin(x^2)/x = 0#

Explanation:

First, multiply the top and bottom of the limit by #x#:

#lim_(x->0) (x*sin(x^2))/x^2#

Now create a new variable #u = x^2#.
Note that #x = sqrtu#, and as #x->0#, #u->0#, since #(0)^2 = 0#.
We can therefore rewrite the limit as:

#lim_(u->0) sqrtu * (sinu/u)#

#= lim_(u->0)sqrtu * lim_(u->0)sinu/u#

The second limit is one of the famous calculus limits #lim_(x->0)sinx/x = 1#.

#= lim_(u->0)sqrtu * (1)#

#= 0 * 1#

#= 0#

Final Answer

Jul 22, 2017

Use L'hopital's rule to find that #lim_(x->0)sin(x^2)/x=0#

Explanation:

For #x=o, sin(x^2)/x=0/0# so we can use L'hopital's rule:

#lim_(x->a) (f(x))/(g(x))=lim_(x→a)(f'(a))/(g'(a))# given that #limf(x)# and #limg(x)# exist

#lim_(x→0) sin(x^2)/x = lim_(x→0) ((sin(x^2))')/(x') = lim_(x→0)2xcos(x^2)#

Letting #x# equal zero gives #lim_(x→0) sin(x^2)/x = 0#

Jul 22, 2017

#0#

Explanation:

formula# rArr lim_(x->0) sinx/x = 1#

#rArr lim_(x->0) sinx^2/x#

Now, multiply and divide x
#rArr lim_(x->0) (sinx^2 * x)/(x * x)#
#rArr lim_(x->0) (sinx^2 * x)/x^2#
#rArr lim_(x->0) 1 * x#

#rArr 0#

ENJOY MATHS!!!!!