Math miscellaneousHard
Question
If A2 - A + I = 0, then the inverse of A is
Options
A.A + I
B.A
C.A - I
D.I - A
Solution
Given A2 - A + I = 0
A-1A2 - A-1A + A-1 - I = A-1.0 (Multiplying A-1 on both sides)
⇒ A - I + A-1 = 0 or A-1 = I - A.
A-1A2 - A-1A + A-1 - I = A-1.0 (Multiplying A-1 on both sides)
⇒ A - I + A-1 = 0 or A-1 = I - A.
Create a free account to view solution
View Solution FreeMore Math miscellaneous Questions
If a, b, c are distinct +ve real numbers and a2 + b2 + c2 = 1 then ab + bc + ca is...If one of the lines given by $6x^2 - xy + 4cy^2 = 0$ is $3x + 4y = 0$, then $c$ equals...The point of lines represented by 3ax2 + 5xy + (a2 - 2)y2 = 0 and perpendicular to each other for...The largest value of positive integer k for which (xk + 1) divides (1 + x + x2 + .......+x127), is divisible by -...If variance of the group ∝, 1 + ∝, ......, n + ∝ is , then value of n will be :-...