`2+secxcscx=(sinx+cosx)^2/(sinxcosx)`
To prove, consider the left side of the equation.
`2+secxcscx`
Express the secant and cosecant in terms of cosine and sine, respectively.
`=2+1/cosx*1/sinx`
`=2+1/(sinxcosx)`
To add, express them as two fractions with same denominators.
`=2*(sinxcosx)/(sinxcosx)+1/(sinxcosx)`
`=(2sinxcosx)/(sinxcosx) + 1/(sinxcosx)`
`=(2sinxcosx + 1)/(sinxcosx)`
Apply the Pythagorean identity `sin^2x+cos^2x=1` .
`=(2sinxcosx+sin^2+cos^2x)/(sinxcosx)`
`=(sin^2x+2sinxcosx+cos^2x)/(sinxcosx)`
And, factor the numerator.
`= ((sinx +cosx)(sinx+cosx))/(sinxcosx)`
`=(sinx+cosx)^2/(sinxcosx)`
Notice that this is the same expression that the right side of the equation have. Thus, this proves that the `2+secxcscx=(sinx+cosx)^2/(sinxcosx)` is an identity.
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