All categories

2 years ago

Find the value of f(x) at the given value of x: f(x) = (x -4)(x + 3), x = 3

Mathematics

1 answer:

mario62 [17]2 years ago

7 0

Answer:

-6

Step-by-step explanation:

f(x)= (3- 4)(3+3)

=( -1 )(6)

= -6

You might be interested in

Malik had two tests on Wednesday. On the science test, each question was worth 4 points. On the math test, each question was wor

Gre4nikov [31]

Answer:

Science Test

Step-by-step explanation:

If he missed 12 points on each test (-12) he missed 2 questions on the math test and 4 questions on the sceince test.

7 0

3 years ago

10. Determine the open interval(s) on which the function f(x) = 12x - x^3 is increasing.

Gre4nikov [31]

Answer:

$\large\boxed{x\in(-2,\ 2)}$

Step-by-step explanation:

$f(x)=12x-x^3$

Calculate the derivative of the function:

$f'(x)=\left(12x-x^3\right)'=(12x)'-\left(x^3\right)'=12-3x^2$

Calculate the zeros of the derivative:

$f'(x)=0\Rightarrow12-3x^2=0\qquad\text{add}\ 3x^2\ \text{to both sides}\\\\3x^2=12\qquad\text{divide both sides by 3}\\\\x^2=4\to x=\pm\sqrt4\\\\x=\pm2$

Let's check the derivative sign:

$f'(x)>0\iff12-3x^2>0\qquad\text{use the distributive property}\\\\-3(x^2-4)>0\\\\-3(x^2-2^2)>0\qquad\text{use}\ a^2-b^2=(a-b)(a+b)\\\\-3(x-2)(x+2)>0\\^{\qquad x=2\qquad x=-2$

Sketch a parabola open down

(before the brackets there is the number -3 < 0)

Look at the picture.

Where the derivative is negative, the function decreases.

Where the derivative is positive, the function increases.

Therefore your answer is:

$x\in(-2,\ 2)$

3 0

3 years ago

Please help help help meee

Allisa [31]

Answer:

Kaylaa do you use desmos graphing calculator? it's an online graphsing tool and would make this very easy for you. Maybe you are not allowed to use a calculator?

Step-by-step explanation:

with out a calculator it's a long math process, 1st because each of the equations are equal to Y, we can set each of them equal to each other. like this

$\sqrt{x-8}$ + 3 = - $(x-5)^{2}$ + 18

$\sqrt{x-8}$ = - $(x-5)^{2}$ +18 -3

$\sqrt{x-8}$ = - $(x-5)^{2}$ + 15

$\sqrt{x-8}$ = -[ (x-5)*(x-5) ] + 15

$\sqrt{x-8}$ = -[ $x^{2}$ - 10x + 25] +15

$\sqrt{x-8}$ = - $x^{2}$ + 10x -25 +15

$\sqrt{x-8}$ = - $x^{2}$ + 10x -10

- $\sqrt{x-8}$ = $x^{2}$ - 10x +10

(- $\sqrt{x-8}$ )^2 = ( $x^{2}$ - 10x +10)^2

this turns into a 4 order polynomial. I used a solver to find x

x = 8.75884.... approx

so the question asks what is the point at the nearest 1000th, which is 8.759

then they ask what is the point at the nearest 100th, which is

8.76

I'm attaching the graph, if it helps :P

8 0

2 years ago

Cual es la moda de las siguientes cantidades 9.6 9.1 8.7 7.9 7.3 5.5 7.9

Brilliant_brown [7]

The mode is 7.9 according to my calculations. You find the number that appears the most in the set. If I am right, brainliest answer and thanks?

3 0

3 years ago

What is the value of X? (giving brainliest and thanks to all!)

KatRina [158]

applying sin theta

so,

sin30°= 8/x

1/2 = 8/x

x=16

3 0

3 years ago

Find the value of f(x) at the given value of x: f(x) = (x -4)(x + 3), x = 3​

Find the value of f(x) at the given value of x: f(x) = (x -4)(x + 3), x = 3