If `A=[[cosalpha,sinalpha],[-sinalpha,cosalpha]]`
is such that `A^T=A^(-1)`,find `alpha`
Text Solution
Verified by Experts
Given that,
`A=[[cosalpha,sinalpha],[-sinalpha,cosalpha]]`
`A^T=A^(-1)`
`A^T=[[cosalpha,-sinalpha],[sinalpha,cosalpha]]`
`|A|=1`
`A^-1=[[cosalpha,-sinalpha],[sinalpha,cosalpha]]`
There can be any real values of `alpha`
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