SOLUTION: If tan²x = 1 + 2tan²y Show that cos2x + sin²y = 0

Question 1161703: If tan²x = 1 + 2tan²y
Show that
cos2x + sin²y = 0
Answer by Edwin McCravy(20081) (Show Source): You can put this solution on YOUR website!
If tan²x = 1 + 2tan²y
Show that
cos2x + sin²y = 0

tan²x = 1 + 2tan²y

Use the identity

           

rewritten as 

          









Use the identity

           

rewritten as 

          

on the left side

Use the identity 

          

rewritten as

          

on the right side



Subtract 1 from both sides:



add sin²(x) to both sides:



Swap sides:

 

Edwin

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