Value of a matrix polynomial such as A^2 + pA + qI
This type of question, asked 3 times: May 2021 S1, 16 Apr 2026 S2, 18 Apr 2026 S2. All 3 questions below, oldest first.
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Question 1
May 2021 S1
117If matrix A=(12−13), then A2−4A+5I is where I is a unit matrix.
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Question 2
16 Apr 2026 S2
65If A=[20−12] and A2+xA+yI2=O2, where I2 and O2 are the identity matrix and null matrix of order 2 respectively, then:
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Question 3
18 Apr 2026 S2
64Let A=[−3124] and if A2−2A+I=[18qp11], then …
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