Prove that # 1200secx(2(sec^2x)-1) -= 1220 ((1+sin^2x)/cos^2x) #?

1 Answer
Feb 4, 2018

The given statement is not an identity.

Explanation:

We seek to prove that:

# 1200secx(2(sec^2x)-1) -= 1220 ((1+sin^2x)/cos^2x) #

We can disprove this identity using a Counter Example:

Consider the case #x=0#, then:

# LHS = 1200sec0(2(sec^2 0)-1) #
# \ \ \ \ \ \ \ \ = 1200(2-1) #
# \ \ \ \ \ \ \ \ = 1200 #

And:

# RHS = 1220 ((1+sin^2 0)/cos^2 0) #
# \ \ \ \ \ \ \ \ = 1220 ((1+0)/1) #
# \ \ \ \ \ \ \ \ = 1220 #

And #LHS != RHS # so the given statement is not an identity.