All categories

2 years ago

Which of the following is a solution of x^2 + 2x + 8?

1 answer:

5 0

X^2 + 2x + 8 = 0
x^2 + 2x = -8
x^2 + 2x + 1 = -8 + 1
(x + 1)^2 = -7
x + 1 = (+-) sqrt -7
x = -1 (+-) sqrt -7

solution is : x = -1 + i * sqrt 7

You might be interested in

HELP FAST BUT BE CORRECT(:

Marrrta [24]

the correct answer is C.

3 0

2 years ago

Plz help me with this

AnnZ [28]

Answer: $\bold{A)\quad y=5sin\bigg(\dfrac{6}{5}x-\pi\bigg)-4}$

Step-by-step explanation:

The general form of a sin/cos function is: y = A sin/cos (Bx-C) + D where the period (P) = 2π ÷ B

In the given function, $B=\dfrac{6}{5}$ → $P=2\pi \cdot \dfrac{5}{6}=\dfrac{10\pi}{3}$

Half of that period is: $\dfrac{1}{2}\cdot \dfrac{10\pi}{3}=\large\boxed{\dfrac{5\pi}{3}}$

Calculate the period for each of the options to find a match:

$A)\quad B=\dfrac{6}{5}:\quad 2\pi \div \dfrac{6}{5}=2\pi \cdot \dfrac{5}{6}=\dfrac{5\pi}{3}\quad \leftarrow\text{THIS WORKS!}\\\\\\B)\quad B=\dfrac{6}{10}:\quad 2\pi \div \dfrac{6}{10}=2\pi \cdot \dfrac{10}{6}=\dfrac{10\pi}{3}\\\\\\C)\quad B=\dfrac{5}{6}:\quad 2\pi \div \dfrac{5}{6}=2\pi \cdot \dfrac{6}{5}=\dfrac{12\pi}{5}\\\\\\D)\quad B=\dfrac{3}{10}:\quad 2\pi \div \dfrac{3}{10}=2\pi \cdot \dfrac{10}{3}=\dfrac{20\pi}{3}$

7 0

3 years ago

Find a polynomial equation that has zeros at x = -4, x = 0, and a double root at x = 7.

Ksju [112]

Answer:

Step-by-step explanation:

Given a polynomial f(x) with roots say x = a and x = b, then the factors are

(x - a) and (x - b) and f(x) is the product of the roots, that is

f(x) = (x - a)(x - b)

Here the roots are x = - 4, x = 0 and double root at x = 7

Thus factors are (x - (- 4)), (x - 0), that is (x + 4) and x

Given a double root at x = 7 the factor is (x - 7)², thus polynomial is

y = x(x + 4)(x - 7)² → D

7 0

2 years ago

What is the product 5x and x^2+1

djyliett [7]

89 8989898989898989898

8 0

2 years ago

Which expression is equivalent to - 14 -6? A.-14 + (-6) B.-14 -6 C.14 +6 D.14 +(-6)

kykrilka [37]

Answer:

Step-by-step explanation:

4 0

2 years ago