Posted by **vidhu** on Thursday, August 9, 2012 at 11:57am.

(sec 8 x - 1)/(sec 4x -1) = tan 8x/tan 4x Prove it!

- trig -
**Reiny**, Thursday, August 9, 2012 at 12:39pm
One of the first things I usually do is test if the identity is true by picking any value of x.

Since it is an identity it should work for all value of x

let x=10

LS = (1/cos80 -1)/(1/cos40-1)

= appr 15.58

RS = tan80/tan40 = appr 6.758

so , not true, no point trying to prove it.

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