Welcome :: Homework Help and Answers :: Mathskey.com
Welcome to Mathskey.com Question & Answers Community. Ask any math/science homework question and receive answers from other members of the community.

13,435 questions

17,804 answers

1,438 comments

778,307 users

show that trigonometric identity!!!!!!!!!!!!!!

0 votes

tan(x)+sec(x)-1/tan(x)+sec(x)-1=1+sin(x)/cos(x)

asked Jun 14, 2013 in TRIGONOMETRY by angel12 Scholar

1 Answer

0 votes

LHS = (tan(x)+sec(x)-1) / (tan(x)-sec(x)+1)

Apply Pythagorean formula : sec2(x) - tan2(x) = 1

= [tan(x)+sec(x) -(sec2(x) - tan2(x))] / (tan(x)-sec(x)+1)

formula : a2- b2 = (a + b)(a - b)

= [tan(x)+sec(x) - {(tan(x)+sec(x))(sec(x) - tan(x))}] /  (tan(x)-sec(x)+1)

Take out common factors.

= [tan(x)+sec(x){1 - (sec(x) - tan(x))}] / (tan(x)-sec(x)+1)

= [tan(x)+sec(x){(tan(x)-sec(x)+1)}] / (tan(x)-sec(x)+1)

Cancel common terms.

= tan(x)+sec(x)

= [sin(x)/cos(x)] +[1/cos(x)]

= [1 + sin(x)] /cos(x)

RHS = [1 + sin(x)] /cos(x)

 

answered Jun 20, 2013 by anonymous

Related questions

asked May 10, 2014 in CALCULUS by anonymous
...