Q11 of 96 Page 17

Write the set of values of a for which the function f(x) = ax + b is decreasing for all xϵR.

f(x) = ax + b


f’(x) = a + 0


f’(x) = a


For, f(x) to be decreasing, it must have


f’(x) < 0


a < 0


a ϵ (-∞, 0)


Hence the required set of values is a ϵ (-∞, 0).


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