SOLUTION: Can you help me prove the identity: 1+tan^2x=1/cos^2x I don't understand how to solve this.

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Question 816479: Can you help me prove the identity:
1+tan^2x=1/cos^2x
I don't understand how to solve this.
Found 2 solutions by lwsshak3, Alan3354:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Can you help me prove the identity:
1+tan^2x=1/cos^2x
***
1%2Btan%5E2%28x%29=1%2Fcos%5E2%28x%29
..
Start with the left side: (the more complex side)
1%2Btan%5E2%28x%29
..
1%2B%28sin%5E2%28x%29%2Fcos%5E2%28x%29%29
..
%28cos%5E2%28x%29%2Bsin%5E2%28x%29%29%2Fcos%5E2%28x%29=1%2Fcos%5E2%28x%29
..
verified:
left side=right side

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Can you help me prove the identity:
1+tan^2x=1/cos^2x
-------------
1+tan^2x = sec^2
QED