Category: Matrices and Determinants

Question Number 40418 by Tinkutara last updated on 21/Jul/18 Commented by tanmay.chaudhury50@gmail.com last updated on 21/Jul/18 $$plscheckthequestion\dots$$ Answered by tanmay.chaudhury50@gmail.com last updated on…

Question Number 171441 by alcohol last updated on 15/Jun/22 $$I_n=-\frac{2n}{2n+1}{I}_{n-1}$$$$I_0=1$$$$Showthat{I}_n=\frac{{(-4)}^n{(n!)}^2}{(2n+1)!}$$ Commented by infinityaction last…

Question Number 171064 by 119065 last updated on 07/Jun/22 $$When{A}^{-1}=\left[\begin{array}{cc}3& 1\\ 8& 4\end{array}\right]$$$$findtheA=?,\mid A^{-1}\mid \cdot A=?$$ Answered by som(math1967) last updated on 07/Jun/22 $$\:{Adj}\:{A}^{−\mathrm{1}} =$$\left[\begin{array}{cc}4& -8\\ -1& 3\end{array}\right]$$^{{T}}…

Question Number 105071 by dw last updated on 25/Jul/20 Commented by mr W last updated on 25/Jul/20 $$\dots thatsatisfytheequation\dots$$$$whichequation?$$ Commented by dw…

Question Number 170022 by Moytea last updated on 14/May/22 $$2.\left[\begin{array}{c}12\\ 2-1\end{array}\right]$$$$Soln:\left[\begin{array}{c}12\\ 2-1\end{array}\right]=\left[\begin{array}{c}10\\ 01\end{array}\right].A$$$$\Rightarrow \left[\begin{array}{c}12\\ 0-5\end{array}\right]=\left[\begin{array}{c}10\\ -21\end{array}\right].A[R_2\to R_2-2R_1]$$$$\Rightarrow \left[\begin{array}{c}12\\ 01\end{array}\right]=\left[\begin{array}{c}10\\ \frac{2}{5}-\frac{1}{5}\end{array}\right].A[R_2\to (-\frac{1}{5})R_2]$$$$\Rightarrow$$\left[\begin{array}{c}10\\ 01\end{array}\right]$$=$$\left[\begin{array}{c}\frac{1}{5}\frac{2}{5}\\ \frac{2}{5}-\frac{1}{5}\end{array}\right]$$.{A}\:\:\:\:\:\:\left[{R}_{\mathrm{1}} \rightarrow{R}_{\mathrm{1}} −\mathrm{2}{R}_{\mathrm{2}}…