Can u plz help me plz?

Find all the zeros of the equation x^4-6x^2-7x-6=0

rusak2 [61]

Answer:

The zeros are

$x=-2,\:x=3,\:x=-\frac{1}{2}+i\frac{\sqrt{3}}{2},\:x=-\frac{1}{2}-i\frac{\sqrt{3}}{2}$

Step-by-step explanation:

We have been given the equation x^4-6x^2-7x-6=0

Use rational root theorem, we have

$a_0=6,\:\quad a_n=1$

$\mathrm{The\:dividers\:of\:}a_0:\quad 1,\:2,\:3,\:6,\:\quad \mathrm{The\:dividers\:of\:}a_n:\quad 1$

$\mathrm{Therefore,\:check\:the\:following\:rational\:numbers:\quad }\pm \frac{1,\:2,\:3,\:6}{1}$

$-\frac{2}{1}\mathrm{\:is\:a\:root\:of\:the\:expression,\:so\:factor\:out\:}x+2$

$=\left(x+2\right)\frac{x^4-6x^2-7x-6}{x+2}\\$

$=x^3-2x^2-2x-3$

Again factor using the rational root test, we get

$=\left(x+2\right)\left(x-3\right)\left(x^2+x+1\right)$

Using the zero product rule, we have

$x+2=0:\quad x=-2\\x-3=0:\quad x=3\\x^2+x+1=0\\\\x_{1,\:2}=\frac{-1\pm \sqrt{1^2-4\cdot \:1\cdot \:1}}{2\cdot \:1}\\\\=-\frac{1}{2}+i\frac{\sqrt{3}}{2},\:x=-\frac{1}{2}-i\frac{\sqrt{3}}{2}$

Therefore, the zeros are

$x=-2,\:x=3,\:x=-\frac{1}{2}+i\frac{\sqrt{3}}{2},\:x=-\frac{1}{2}-i\frac{\sqrt{3}}{2}$

4 0

2 years ago

Read 2 more answers

A circular lid has a diameter of 12 inches. What is the exact area of the lid? A. 6π square inches B. 12π square inches C. 24π s

kaheart [24]

The area of any circle is equal to $\pi r^2$ , where r is the radius.

We know that the diameter is 12. The radius is always half of the diameter, so the radius of our circle must be 6.

Substitute 6 for r in our equation and simplify.

π6² = π6×6 = 36π in²

6 0

2 years ago

Solve (26/57)=(849/5x)

Gnesinka [82]

<span>Cross multiply 26*5x = 849 * 57 130 x = 48393 x = 48393 / 130 x = 372.25</span>

4 0

2 years ago

Read 2 more answers

Cyril has six more than twice as many mangoes as Kubie and half as many mangoes as Maxine. If Kubie has six mangoes, then, in te

sveticcg [70]

Answer:

(7x + 18) or 60 Mangoes

Step-by-step explanation:

Let the no. of mangoes Kubie possesses be x

So,

Cyril has mangoes = 2x + 6 ...(i)

So,

Maxine has = 2 * (2x + 6)

= 4x + 12

Given that,

Kubie has mangoes = 6

∵ The combined mangoes they have in terms of x,

= Cyril + Kubie + Maxine

= (2x + 6) + x + (4x + 12)

= 7x + 18

A.T.Q.

Cyril has = 2x + 6

∵ Cyril has mangoes = 2 * (6) + 6

= 18 mangoes

∵ Maxine has = 2 * Cyril's mangoes

= 2 * 18

= 36

Thus,

Total mangoes = Cyril + Kubie + Maxine

= 18 + 6 + 36

= 60 Mangoes

5 0

2 years ago

I need help fast ....

Cloud [144]

Since x=-10, plug that into the equation.

f(x) = 2(-10) + 11
= -20 + 11
y = -9

So the ordered pair in (x,y) terms is (-10,-9).

4 0

2 years ago