Test funcții

• 2

• -7

Answer explanation

The domain of the function is {-2, -1, 0} because these are the only input values defined in the function f(x)=x+1.

Answer explanation

The codomain of the function is the set of all real numbers, denoted by R, as the function maps elements from the domain [3;+∞) to real numbers.

Answer explanation

The correct answer is {1;4;7} because when we substitute the given values {-2, 1, 4} into the function f(x) = x + 3, we get {1;4;7} as the output.

Dintre diagramele următoare, cea în care este definită o funcție este:

• A

• B

• C

Answer explanation

The correct choice is C because it is the only diagram where a function is defined, indicated by the mapping of input values to output values.

• • - 49

• 21

• -21

• 49

Answer explanation

To find f(-2), substitute x=-2 into the function f(x)=x+5. Therefore, f(-2)=-2+5=-3. Hence, the correct answer is -3.

Answer explanation

The point D(-1,1) belongs to the graph of the function f(x) = 2x + 3 as it satisfies the equation f(-1) = 2(-1) + 3 = 1.

Answer explanation

The correct choice is (4;0) because the point of intersection with the y-axis is where x=0, so f(0) = 0-4 = -4, giving the coordinates (0;-4).

• 2

• 0

Answer explanation

To find the real value of m, set f(m) equal to the y-coordinate of point A. So, 5m-2=8, solving for m gives m=2. Therefore, the correct value of m is 2.

• 546

• 594

• 550

• 538

Answer explanation

To find the sum, substitute each value from 0 to 26 into the function and add the results. This gives 594 as the final sum.