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3 years ago

Evaluate the function: f(x)=x2+2x, find f(−1)

Mathematics

1 answer:

Elena-2011 [213]3 years ago

7 0

Answer:

$f( - 1) = - 1$

Step-by-step explanation:

$f(x) = {x}^{2} + 2x$

Substitute x = -1 in the equation.

$f( - 1) = {( - 1)}^{2} + 2( - 1) \\ f( - 1) = 1 - 2 \\ f( - 1) = - 1$

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A 2-column table with 6 rows. The first column is labeled x with entries negative 4, negative 2, 0, 2, 4, 6. The second column i

Elina [12.6K]

Answer:

Option C.

Step-by-step explanation:

The given table is

x f(x)

-4 0

-2 2

0 8

2 2

4 0

6 -2

A graph of a function intersect x-axis if the function contains the points whose y-coordinate is 0.

From the given table it is clear that the value of f(x) is 0 at x=-4 and x=4. It means, the continuous function intersect the x-axis at two point (-4,0) and (4,0).

Therefore, the correct option is C.

8 0

3 years ago

Read 2 more answers

How does one do math?

frez [133]

"The only way to learn mathematics is to do mathematics."
-Paul Halmos

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4 years ago

40 miners need to ride the elevator to the bottom of the mine. The elevator can hold 9 miners at a time. How many miners will be

BartSMP [9]

Answer:

the answer is 4

Step-by-step explanation:

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3 years ago

Solve x -9 = 8 HELP!!!!! I am dead over here help me!!!!

kumpel [21]

Answer:

x=17

Step-by-step explanation:

x-9=8

add nine on both sides

x-9+9=8+9

the nines on the side with the x cancel each other

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3 years ago

This net can be folded to make a square pyramid. what is the surface area of the pyramid

givi [52]

Answer:

$85in^2$

Step-by-step explanation:

to find the surface area we need to find the followng areas:

area of the square

area of a triangle and multiply it by 4 (because there are 4 triangles)

And once we have those areas, we add them to find the surface area.

Area of the square:

the formula to find the area of a square is:

$a_{square}=l^2$

where $l$ is the length of the side: $l=5in$

thus the area of the square is:

$a_{square}=(5in)^2$

$a_{square}=25in^2$

Area of the triangles:

the are of 1 triangle is given by

$a_{triangle} =\frac{b*h}{2}$

where $b$ is the base of the triangle: $b=5in$ (the base of the triangle is the side of the square)

and $h$ is the height of the triangle: $h=6in$

thus, the area of 1 triangle is:

$a_{triangle} =\frac{(5in)*(6in)}{2}$

$a_{triangle} =\frac{30in^2}{2}$

$a_{triangle} =15in^2$

the area of the 4 triangles is (we multiply by 4):

$a_{4-triangles}=4(15in^2)$

$a_{4-triangles}=60in^2$

finally we add the area of the square and the area of the 4 triangles to find the total surface area:

$Surface=25in^2+60in^2$

$Surface=85in^2$

8 0

2 years ago