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3 years ago

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Find all the roots of the equation x4 - 2x3 + 14x2 - 18x + 45 = 0 given that 1 + 2i is one of its roots.

1 answer:

patriot [66]3 years ago

7 0

Asked and answered elsewhere.
brainly.com/question/10192511

Knowing that 1+2i is a root, you also know that 1-2i is a root, so one quadratic factor is
(x -1)² -(2i)² = x^2 -2x +5

Long division of the given polynomial by this quadratic gives a quotient of
x² +9
which has roots ±3i.

Then all the roots are {-3i, 3i, 1-2i, 1+2i}.

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A circule has a diameter of 28 ft what is the circumference

lidiya [134]

Answer:

Circumference of a 28 Foot Diameter Circle ; 87.965, feet ; 1,055.6, inches ; 87′ 11.6″, feet and inches ; 26.812, meters ; 2,681.2, centimeters .

Step-by-step explanation:

6 0

1 year ago

The admission fee at a small to the school play is $1.50 for children (x) and $4.00 for adults (y). On opening night, the revenu

Alecsey [184]

Answer:

1.50x + 4.00y =5,050

Step-by-step explanation:

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3 years ago

Limit definition for slope of the graph, equation of tangent line point for<br> f(x)=2x^2 at x=(-1)

Tems11 [23]

The slope of the tangent line to $f$ at $x=-1$ is given by the derivative of $f$ at that point:

$f'(-1)=\displaystyle\lim_{x\to-1}\frac{f(x)-f(-1)}{x-(-1)}=\lim_{x\to-1}\frac{2x^2-2}{x+1}$

Factorize the numerator:

$2x^2-2=2(x^2-1)=2(x-1)(x+1)$

We have $x$ approaching -1; in particular, this means $x\neq-1$ , so that

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

Then

$f'(-1)=\displaystyle\lim_{x\to-1}\frac{2x^2-2}{x+1}=\lim_{x\to-1}2(x-1)=2(-1-1)=-4$

and the tangent line's equation is

$y-f(-1)=f'(-1)(x-(-1))\implies y-4x-2$

6 0

3 years ago

Pls help:Find all the missing elements:

Yuliya22 [10]

Answer:

<h3>B = 48.7° , C = 61.3° , b = 12</h3>

Step-by-step explanation:

In order to find B we must first angle C

To find angle C we use the sine rule

That's

$\frac{ |a| }{ \sin(A) } = \frac{ |c| }{ \sin(C) }$

From the question

a = 15

A = 70°

c = 14

So we have

$\frac{15}{ \sin(70) } = \frac{14}{ \sin(C) }$

$\sin(C) = \frac{14 \sin(7 0 ) }{15}$

$C = \sin^{ - 1} ( \frac{14 \sin(70) }{15} )$

C = 61.288

<h3>C = 61.3° to the nearest tenth</h3>

Since we've found C we can use it to find B.

Angles in a triangle add up to 180°

To find B add A and C and subtract it from 180°

That's

A + B + C = 180

B = 180 - A - C

B = 180 - 70 - 61.3

<h3>B = 48.7° to the nearest tenth</h3>

To find b we can use the sine rule

That's

$\frac{ |a| }{ \sin(A) } = \frac{ |a| }{ \sin(B) }$

$\frac{15}{ \sin(70) } = \frac{ |b| }{ \sin(48.7) }$

$|b| = \frac{15 \sin(48.7) }{ \sin(70) }$

b = 11.9921

<h3>b = 12.0 to the nearest tenth</h3>

Hope this helps you

6 0

3 years ago

Could you help solve this for me

finlep [7]

Answer:

Bro

Step-by-step explanation:

No

5 0

3 years ago