The binary operation (oplus) is defined by x (ast) y = xy – y – x for all real values x and y. If x (ast) 3 = 2(ast), find x
-
A.
-1 -
B.
4 -
C.
1 -
D.
5
Correct Answer: Option C
Explanation
x (ast) y = xy – y – x, x (ast) 3 = 3x – 3 – x = 2x – 3
2 (ast) x = 2x – x – 2 = x – 2
∴ 2x – 3 = x – 2
x = -2 + 3
= 1