Friday
May 24, 2013

# Homework Help: math

Posted by krishan on Monday, June 18, 2012 at 8:41am.

prove that cosx(tanx+2)(2tanx+1)=2secx+5sinx

• math - Reiny, Monday, June 18, 2012 at 9:45am

Looks like "homework or assignment dumping" to me
Exactly what problems do you have with this list of trig questions?

I will do this one.... show me some attempts at the others

LS = cosx(2tan^2 x + 5tanx + 2)
= 2cosx sin^2 x/cos^2 x + 5cosxsinx/cosx + 2cosx
= 2sin^2 x/cosx + 5sinx + 2cosx
= (2sin^2 x + 5sinxcosx + 2cos^2 x)/cosx
= (2 + 5sinxcosx)/cosx
= 2/cosx + 5sinx
= 2secx + 5sinx
= RS

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