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If A=[(costheta,isintheta),(isintheta,co...

If `A=[(costheta,isintheta),(isintheta,costheta)]` , then prove by principle of mathematical induction that `A^n=[(cosn\ theta,isinn\ theta),(isinn\ theta,cosn\ theta)]` for all `n in N` .

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Given that,
`A= [(costheta,isintheta),(isintheta,costheta)]`
We have to prove that `A^n=[(cosn\ theta,isinn\ theta),(isinn\ theta,cosn\ theta)]` for all positive integers `ndot`
It is true for `n=1`.
`implies A^2= [(costheta,isintheta),(isintheta,costheta)]xx [(costheta,isintheta),(isintheta,costheta)]`
`implies A^2= [(cos2theta,isin2theta),(isin2theta,cos2theta)]`
It is true for `n=2`.
Let it is true for `n=n-1`
...
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