Home » Ask & Discuss » Mathematics
« Back to Discussion

Differential Calculus

Scorching goIITian

Joined:	8 Feb 2007
Post:	217

29 May 2007 10:34:55 IST

0 People liked this

1129

Differentiate-

Engineering Entrance , JEE Main , JEE Advanced , Mathematics , Differential Calculus

Find dy/dx-

tanx.tan2x.tan3x

Comments (4)

'',' Off to a nu start!!

Blazing goIITian

Joined: 13 Jan 2007

Posts: 1289

29 May 2007 10:38:22 IST

Like 0 people liked this

just apply product rule temr by term

ruhi agrawal

Blazing goIITian

Joined: 26 Oct 2006

Posts: 530

29 May 2007 10:39:49 IST

Like 0 people liked this

tan(x+2x)=(tanx + tan2x)/(1-tanx tan2x)
solving it..we get....................
tanx.tan2x.tan3x=tan3x - tanx - tan2x
soo nw....
differentiation of (tan3x - tanx - tan2x)
= 3sec^2 3x - sec^2 x - 2sec^2 2x

puneet

Forum Expert

Joined: 19 Oct 2006

Posts: 1966

29 May 2007 13:43:08 IST

Like 0 people liked this

hii

well ruhi has shown a good trick .. though she did some mistake ..

so going with the trick

tan(x+2x) = (tanx + tan2x)/(1-tanx tan2x)
solving it, we get
tanx.tan2x.tan3x=tan3x - tanx - tan2x

and thus dy/dx = 3.sec²3x - sec²x - 2.sec²2x

cheers

prasad rao

Blazing goIITian

Joined: 12 May 2007

Posts: 328

29 May 2007 14:21:05 IST

Like 0 people liked this

another easy way is applying log on both sides

rate if useful

Quick Reply

Reply

	Some HTML allowed.
	Keep your comments above the belt or risk having them deleted.
	Signup for a avatar to have your pictures show up by your comment
	If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team