- #1

chwala

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**Mod note**: Moved from a technical math forum, so this post is missing the homework template

i am trying to prove that ##1/sec∅-tan∅ ≡ sec ∅ + tan∅##

this is how i attempted it, i tried to show that the left hand side is equal to the right......

## 1/ 1/(cos∅-sin∅)/cos∅##

where i end up with

## (cos∅)/(1-sin ∅)## where this is ≡ ## (1+sin ∅)/(cos∅)##

taking ## cos^2∅/1-sin∅## divide by ##1+sin∅/cos∅## is equal to 1 (this is my proof), my concern is can we reduce

and show that ## cos∅/1-sin∅≡1+sin∅/cos∅## without necessarily dividing as i did it

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