P=[25−1−3]
5I−8P=[5005]−[1640−8−24]=[−11−40829]
P2=[25−1−3][25−1−3]=[−1−514]
P3=[25−1−3][−1−514]=[310−2−7]
⇒P6=[310−2−7][310−2−7]=[−11−40829]=Pn
⇒n=6
Let I be an identity matrix of order 2× 2 and P=[ … ]. Then the value of n∈ N for which P^n=5I-8P is equal to .
JEE Main 2021 — Mathematics Algebra
2021integereasy
Let I be an identity matrix of order 2×2 and P=[25−1−3]. Then the value of n∈N for which Pn=5I−8P is equal to ___ .
Official previous-year question
Held on 18 Mar 2021 · Verified 6 Jul 2026.
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