MATHEMATICS

JAMB 2015 - Question 31

Mathematics 2015 JAMB Past Questions - Question 31: The binary operation * is defined by x*y=xy-y-x for all real values of x and y .If x*3=2*x,find the value of x .

The binary operation * is defined by x*y=xy-y-x for all real values of x and y .If x*3=2*x,find the value of x .
A:
B:
C:
D:
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Correct Answer

C

Explanation

x*3=2*33x-3-x=2x-x-22x-x=-2+3x=1To find the value of x, we can use the given equation x*3 = 2*x and substitute the definition of the binary operation * into it.So, x*3 = 3x - 3 - x = 2xSolving for x, we get:3x - 3 - x = 2x2x - 3 = 2x-3 = 0This equation leads to a contradiction, -3 cannot be equal to 0. Therefore, there is no real value of x that satisfies the given equation x*3 = 2*x.