Question

Fie functia f : R → R, f(x) = 2x − 1. Sa se determine f({1, 2, 5}), f((−∞, 1]), f([−2, 4]).

Answer 1

Răspuns:

f(x)=2x-1

f({1,2,5})=

f(1)=2*1-1=2-1=1

f(2)=2*2-1=4-1=3

f(5)=2*5-1=10-1=9

f({1,2,5})={1,3,9}

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f(-∞)= -∞

f(1)=2*1-1=1

f((-∞,1])=(-∞,1]

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f(-2)=2*(-2)-1=-4-1=-5

f(4)=2*4-1=7

f([-2,4])=[-5,7]

Explicație: