Q9 of 50 Page 28

The following table represents a function from A = { 5, 6, 8, 10 } to B = { 19, 15, 9, 11 } where f = 2x - 1. Find the values of a and b.

It’s given that f(x) = 2x-1


So f(5) = 2 × 5 -1


= 10-1


= 9


∴ a = 5


Similarly f(8) = 2 × 8 -1


= 16-1


= 15


∴ b = 15


So the values of a = 9 and b = 15


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