Page 117 - Bangladesh_classwiz_BOOK2018_rev_Neat

−1
−1 = = I, ‡hLv‡b I n‡jv identity g¨vwUª·| Identity g¨vwU· †`Lv‡bvi Rb¨ K¨vjKz‡jU‡ii cÖ‡qvM
wb‡P †`Iqv n‡jv-

myZivs, ÷ †ei Kivi Rb¨ K¨vjKz‡jU‡i −1 ‡ei Ki‡Z n‡e| wb‡P †`Lv‡bv n‡jv-

7 ÷ 8 †K 8 w`‡q ¸Y Ki‡j †hgb cybivq 8 cvIqv hvq †Zgwb −1 †K w`‡q ¸Y Ki‡j cvIqv hv‡e|

Dc‡i cÖvß djvdj wb‡Pi w¯Œ‡bi g‡Zv w`‡q ¸Y Ki‡j mv‡_ mv‡_ cvIqv hv‡e| jÿYxq †h K¨vjKz‡jUi
G‡ÿ‡Î Mat Ans e¨envi Ki‡e|

K¨vjKz‡jU‡i bZzbfv‡e cy‡ivUv wj‡LI †`Lv hvq −1 = = .

‡h‡nZz g¨vwUª· ¸Yb wewbgq m~Î †g‡b P‡jbv, ZvB wbw`©ó µ‡gB G‡`i ¸Y Ki‡Z n‡e| G‡ÿ‡Î −1 Gi djvdj

KL‡bv Avm‡ebv|

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eM© g¨vwUª‡·i msL¨v ivwk‡K wbYvqK e‡j| ‡Kv‡bv eM© g¨vwUª‡·i wecixZ g¨vwUª· †ei Ki‡Z n‡j c~‡e© cixÿv Ki‡Z
nq †h Gi wbY©vq‡Ki gvb k~b¨ wKbv| hw` wbY©vq‡Ki gvb k~b¨ nq, Zvn‡j eM© g¨vwUª·wUi wecixZ g¨vwUª· _vK‡e bv|
cÿvšÍ‡I, k~b¨ Qvov Ab¨ †h†Kv†bv gvb _vK‡j wecixZ g¨vwUª· _vK‡e| T menu Gi wØZxq w¯Œb †_‡K mivmwi
‡Kv‡bv g¨vwUª‡·i wbY©vqK †ei Kiv hvq| 2 †P‡c Determinant wbe©vPb K‡i Avevi T †_‡K Mat A

wbe©vPb Ki‡Z n‡e| Gici = Pvc‡j g¨vwUª‡·i wbY©vq‡Ki gvb cvIqv hv‡e|

‡Kv‡bv g¨vwUª‡·i mvwi¸‡jv‡K Kjv‡g Ges Kjvg¸‡jv‡K mvwi‡Z iƒcvšÍi Ki‡j Zv‡K Uªv݇cvR g¨vwUª· e‡j|

g¨vwUª‡·i Uªv݇cvR‡K ′ Øviv cÖKvk Kiv nq| T menu Gi wØZxq †cR †_‡K mivmwi GwU cvIqv hvq hv
Dc‡ii wØZxq I Z…Zxq wP‡Î †`Lv‡bv n‡jv|

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