Question

arctan(1-x)+arctan(1+x)=arctan(1/8), solve

Answer 1

apply tan on both sides and apply tan(A+B) formula u apply tan(arctan(A))= A rule to get the answer!!!!!!!

Answer 2

\[\tan^{-1} (1-x)+\tan^{-1} (1+x)=\tan^{-1} (1/8)\]
is that it??
but i don't know what to do next

Answer 3

i got it!!! hahahahaha.. im so happy.. thanks for the help!!
the answer is 4 :))

Answer 4

haha... @erosha welcome :))))))))

Answer 5

is my answer correct? can u check it?? :))

Answer 6

My first step would be to subtract either arctan(1+x) or arctan(1-x
Then Take tan( ) of both sides
The use that one identity: \[\tan(a \pm b)=\frac{\tan(a) \pm \tan(b)}{1 \mp \tan(a)\tan(b)}\]

Answer 7

Then* not the

Answer 8

The rest is algebra

Answer 9

Because as @sriramkumar said tan(arctan(a))=a

Answer 10

1-x+1+x/(1-(1-x)(1+x))= 1/8

2/1-(1-x^2)= 1/8

2/x^2 = 1/8

x^2= 8*2=16

x=+/-4
yep its correct!!!!!! @eroshea