Cos^-1(-x)=-Cos^-1x for -1<x<1 TRUE OR FALSE?
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We are given
[tex]cos^{-1}(-x)=-cos^{-1}(x)[/tex]
Firstly, we will simplify left side
and we will check whether it is equal to right side
Left side:
Let's assume y left side expression
[tex]y=cos^{-1}(-x)[/tex]
now, we can take cos on both sides
[tex]cos(y)=cos(cos^{-1}(-x))[/tex]
we can simplify it
[tex]cos(y)=-x[/tex]
Right side:
Let's assume y left side expression
[tex]y=-cos^{-1}(x)[/tex]
Multiply both sides by -1
[tex]-y=cos^{-1}(x)[/tex]
now, we can take cos on both sides
[tex]cos(-y)=cos(cos^{-1}(x))[/tex]
we can simplify it
[tex]cos(-y)=x[/tex]
[tex]cos(y)=x[/tex]
we can see that
both sides cos(y) value is different
so, this is FALSE.........Answer