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3 years ago

What is the answer to this? i can’t figure it out.

Mathematics

1 answer:

Svetach [21]3 years ago

8 0

9514 1404 393

Answer:

25 +0i

Step-by-step explanation:

The conjugate of a complex number is that number with the sign of the imaginary part reversed.

For z = -3+4i, its conjugate z* is -3-4i. The product of z and z* is ...

(-3 +4i)(-3 -4i) = -3(-3 -4i) +4i(-3 -4i)

= 9 +12i -12i -16i² = 9 +16 = 25

The real part of the product is 25; the imaginary part is 0.

(-3 +4i)(-3 -4i) = 25 +0i

_____

You may have noticed that (z)(z*) = |z|², the sum of the squares of the real and imaginary parts. It is always a non-negative real number.

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The masses mi are located at the points Pi. Find the moments Mx and My and the center of mass of the system. m1 = 4, m2 = 3, m3

viva [34]

Answer:

$M_x$ = 8

$M_y$ = 6

Therefore the co-ordinate of the center of mass is = $(\frac{4}{5},\frac{3}{5})$

Step-by-step explanation:

Center of mass: Center of mass of an object is a point on the object. Center of mass is the average position of the system.

Center of mass of a triangle is the centriod of a triangle.

Given that m₁= 4, m₂=3, m₃=3 and the points are P₁(2,-3), P₂(-3,1) and P₃(3,5)

$M_x$ = ∑(mass × x-co-ordinate)

$M_y$ = ∑(mass × y-co-ordinate)

Therefore

$M_x$ = (4×2)+{3×(-3)}+(3×3)

$M_y$ = {4×(-3)}+{3×1}+(3×5)

The x co-ordinate of the center of mass is the ratio of $M_x$ to the total mass.

The y co-ordinate of the center of mass is the ratio of $M_y$ to the total mass.

Total mass (m) = m₁+ m₂+ m₃

= 4+3+3

=10

The x co-ordinate of the center of mass is $\frac {8}{10} = \frac {4}{5}$

The y co-ordinate of the center of mass is $\frac{6}{10}=\frac{3}{5}$

Therefore the co-ordinate of the center of mass is = $(\frac{4}{5},\frac{3}{5})$

4 0

3 years ago

I need help with this question please I’ll give u brain

lina2011 [118]

Answer:2In2-2In3

Step-by-step explanation:

In(4/9)

In4-In9

In2^2-In3^2

2In2-2In3

7 0

3 years ago

A rectangular prism has a base area of 56 square feet and a volume of 840 cubic feet. The length of the base is longer than the

katovenus [111]

The answer is 8 ft.

The base area of rectangular prism is: A = l * w = 56 ft²
<span>The length of the base is longer than the width: l > w

The volume of the prism is: V = l * w * h = 840 ft</span>³
<span>The sum of the length and width of the base is equal to the height of the pyramid: l + w = h

So:
</span>l * w = 56
l * w * h = 840
___
56 * h = 840
h = 840 / 56
h = 15 ft

Now, we know that
l + w = 15 ⇒ w = 15 - l
l * w = 56
___
l * (15 - l) = 56
15l - l² = 56
0 = l² - 15l + 56

Or: l² - 15l + 56 = 0

Let's solve the quadratic function:
l = (-b +/-√(b² - 4ac)/(2a)
= (15 +/-√(-15)² - 4 * 1 * 56))/(2*1)
= (15 +/- √(225 - 224))/2
= (15 +/- √1)/2
= (15 +/-1)/2

l = (15+1)/2 = 16/2 = 8
or
l = (15-1)/2 = 14/2 = 7

If l = 8, then w = 15 - 8 = 7. So, l > w
If l = 7, then w = 15 - 7 = 8. So, l < w

Therefore, l = 8 ft.

6 0

4 years ago

PLEASE HELPP! Its really important

Ivahew [28]

........Option C ) n × 2 = t

8 0

3 years ago

Read 2 more answers

In a right triangle, angle C measures 40°. The hypotenuse of the triangle is 10 inches long. What is the approximate length of t

Galina-37 [17]

Answer:

The cosine function is: adjacent/hypotenuse = cos (40). We know the hypotenuse length is 10, so the equation is now adjacent/10 = cos (40). Solving for adjacent length we get 7.7 inches.

4 0

3 years ago