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If x= sin theta then x/√1-x^2 is​

1 Answer

4 votes

Well,

Given that
x=\sin(\theta),

We can rewrite the equation like,


(\sin(\theta))/(√(1-\sin(\theta)^2))

Now use,
\cos(\theta)^2+\sin(\theta)^2=1 which implies that
1-\sin(\theta)^2=\cos(\theta)^2

That means that,


(\sin(\theta))/(√(1-\sin(\theta)^2))\Longleftrightarrow(\sin(\theta))/(√(\cos(\theta)^2))

By def
√(x^2)=x therefore
√(\cos(\theta)^2)=\cos(\theta)

So the fraction now looks like,


(\sin(\theta))/(\cos(\theta))

Which is equal to the identity,


\boxed{\tan(\theta)}=(\sin(\theta))/(\cos(\theta))

Hope this helps.

r3t40

User Jerome Dalbert
by
5.7k points