Calculus Help

MrCodeDude

Lifer
Jun 23, 2001
13,674
1
76
First of all, thanks in advance.

Determine the limit of the trigonometric function (if it exists)

limit as x -> 0

(tan^2 x) / x

And, just for your information:
(sin x) / x = 1 and (1 - cos(x)) / x = 0
 

Legendary

Diamond Member
Jan 22, 2002
7,019
1
0
Use L'Hospital's rule and take the derivative of the top and the bottom then reapply the limit
 

phatj

Golden Member
Mar 21, 2003
1,837
0
0
or if you are not allowed to use L'Hospital's rule (or havent learned it yet)

do this:

lim x -> 0 of [tan^2(x)/x] = lim x -> 0 of [sin(x) * [sin(x)/x] * 1/(cos^2(x))] = sin(0) * 1 * 1/1^2 = 0

remember: tan(x) = sin(x)/cos(x), so tan^2(x) = sin^2(x)/cos^2(x)
 

Syringer

Lifer
Aug 2, 2001
19,333
2
71
Yeah, was about to post that..convert tan to sin/cos, cos is left in the denominator, and the limit to 0 makes the denominator one..