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How would you solve: tan(15 degrees)/1-tan^2(15 degrees)? (show steps) Thanks

1 Answer
Mar 9, 2018

Answer:

#tan15^@/(1-tan^2 15^@)=1/(2sqrt3)#

Explanation:

We use the identity #(2tanA)/(1-tan^2A)=tan2A#

Now if #A=15^@#

#(2tan15^@)/(1-tan^2 15^@)=tan(2xx15^@)#

or #(2tan15^@)/(1-tan^2 15^@)=tan30^@=1/sqrt3#

Hence #tan15^@/(1-tan^2 15^@)=1/(2sqrt3)#