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2 years ago

I need it ASAP. Solve it please!! {z}^{3} - 8i = 0

Mathematics

1 answer:

labwork [276]2 years ago

6 0

Step-by-step explanation:

one of the cube roots (there are 3 of them) is

81/3[cos(270°/3) + isin(270°/3)] = 2(cos90° + isin90°) = 2i

The 3 cube roots are equally spaced around the circle centered at (0,0) with radius 81/3 = 2

360° / 3 = 120°

Another cube root of -8i is

2[cos(90° + 120°) + isin(90° + 120°)] = 2[cos(210°) + isin(210°)] = 2(-√3/2 + i(-1/2)) = -√3 - i

The third cube root of -8i is

2[cos(90°+2(120°)) + isin(90°+2(120°)) = 2[cos330° + isin(330°)] = 2[√3/2 +i(-1/2)] = √3 - i

So, the cube roots of -8i are 2i, -√3 - i, and √3 - i

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Write the equation of a line that is perpendicular to x=-6x=−6x, equals, minus, 6 and that passes through the point (-1,-2)(−1,−

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9514 1404 393

Answer:

y = -2

Step-by-step explanation:

The given line is a vertical line, so a perpendicular line will be a horizontal line. It will have an equation of the form ...

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2 years ago

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Find n(A) for the following set. A={a,b,c,...,z}

MariettaO [177]

n(A) = 26

Solution:

Let us first define the cardinal number of the set.

Cardinal number of the set:

The number of distinct elements in a finite set is called its cardinal number. It is denoted as n(A).

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We know that, there are 26 elements in the alphabet "a to z".

Number of elements in the set A = 26

Hence n(A) = 26.

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2 years ago

For the polynomial below, find F(-3) F(-3)= -4x^2+3x-1

Elodia [21]

$f(-3)=-4\cdot(-3)^2+3\cdot(-3)-1=-4\cdot9-9-1=-36-10=-46$

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2 years ago

Using substitution x+3y=3 3y-2x=12

frez [133]

Step-by-step explanation:

Given :-

x + 3y = 3
3y - 2x = 12

And we need to solve the equation using Substituting method . So on taking the first equation ,

$\rm\implies x + 3y = 3 \\\\\rm\implies x = 3 - 3y$

Put this value in (ii) :-

$\rm\implies 3y - 2x = 12 \\\\\rm\implies 3y - 2(3-3y)=12\\\\\rm\implies 3y -6-6y = 12 \\\\\rm\implies -3y = 18 \\\\\rm\implies y = -6$

Put this Value in (I) :-

$\\\\\rm\implies x = 3-3*-6 \\\\\rm\implies x = 3+18 \\\\\rm\implies x = 21$

Hence the Value of x is 21 and y is (-6) .

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2 years ago

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A sample of 20 joint specimens of a particular type gave a sample mean proportional limit stress of 8.41 mpa and a sample standa

nignag [31]

For this problem, the confidence interval is the one we are looking for. Since the confidence level is not given, we assume that it is 95%.

The formula for the confidence interval is: mean ± t (α/2)(n-1) * s √1 + 1/n

Where:

α= 5%

α/2 = 2.5%

t 0.025, 19 = 2.093 (check t table)

n = 20

df = n – 1 = 20 – 1 = 19

So plugging in our values:

8.41 ± 2.093 * 0.77 √ 1 + 1/20

= 8.41 ± 2.093 * 0.77 (1.0247)

= 8.41 ± 2.093 * 0.789019

= 8.41 ± 1.65141676

= 6.7586 < x < 10.0614

3 0

2 years ago

I need it ASAP. Solve it please!! {z}^{3} - 8i = 0​

I need it ASAP. Solve it please!! {z}^{3} - 8i = 0