MATHEMATICS

JAMB 2011 - Question 23

Mathematics 2011 JAMB Past Questions - Question 23: A binary operation * on real numbers is defined by x*y=xy+x+y for two real numbers x and y .Find the value of 3*-2/3

A binary operation * on real numbers is defined by x*y=xy+x+y for two real numbers x and y .Find the value of 3*-2/3
A:
B:
C:
D:
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Correct Answer

B

Explanation

n+y = xy +x +y3 + - 2/3 = 3 (-2/3) +3+(-2/3) = - 2 +3 -2/3 = 1 - 2 / 1,3 = 3-2 /3 = 1/3To find the value of 3 * (-2/3) using the given binary operation, we substitute the values into the expression x * y = xy + x + y:3 * (-2/3) = (3)(-2/3) + 3 + (-2/3)Simplifying, we have:= -2 + 3 - 2/3= 1 - 2/3To combine the fractions, we need a common denominator:= 3/3 - 2/3= 1/3Therefore, the value of 3 * (-2/3) using the given binary operation is 1/3.