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Question
Matrix A = `[(0,2b,-2),(3,1,3),(3a,3,-1)]`is given to be symmetric, find values of a and b
Solution
We have
`A=[(0,2b,-2),(3,1,2),(3a,3,-1)]`
`A'=[(0,3,3a),(2b,1,3),(-2,3,-1)]`
We know that a matrix is symmetric if A = A'.
Thus,
`[(0,2b,-2),(3,1,3),(3a,3,-1)]=[(0,3,3a),(2b,1,3),(-2,3,-1)]`
Now,
2b=3
`=>b=3/2`
Also,
3a=−2
`=>a=(-2)/3`
Therefore,
a=`(-2)/3`and b = `3/2`
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