Verify: (cos^2x)(tan^2x) + (cos^2x)= 1
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In trigonometry there is a major trigonometric identity as;
`sin^2x+cos^2x = 1`
We also know that;
`tanx = (sinx)/cosx`
Now we will start the question from Left Hand Side(LHS)
So it is proven that `(cos^2x)tan^2x+cos^2x = 1`
Show `cos^2x(tan^2x)+cos^2x=1` :
`=cos^2x(tan^2x+1)` Factor out common term
`=cos^2x(sec^2x)` Pythasgorean relationship
`=cos^2x*1/(cos^2x)` Definition of sec(x)
`=1` as required.
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