All categories

3 years ago

please help me The question involves multiplying two complex numbers, then turning it into an a+bi equation (pictures included)

Mathematics

1 answer:

Sloan [31]3 years ago

8 0

Answer:

(a, b) = (0, -15)

Step-by-step explanation:

In "cis" form the product of two complex numbers is the product of their magnitudes at the angle that is the sum of their angles. I find this the easiest way to multiply complex numbers.

z1 × z2 = (3 cis π)(5 cis π/2)

= (3·5) cis (π +π/2)

= 15 cis 3π/2

Of course, "cis" is short for "cosine + i·sine", so you have ...

z1 × z2 = 15 cis 3π/2 = 15(cos(3π/2) +i·sin(3π/2))

= 15(0 +i·(-1))

= 0 -15i

(a, b) = (0, -15)

You might be interested in

Sheldon needs a pound of meat for a recipe he is planning to make next week. He sets aside a pound of meat and puts it in the fr

padilas [110]

Answer:

He needs to check his work more, and stop asking middle schoolers to do his cooking math.

Step-by-step explanation:

6 0

2 years ago

Read 2 more answers

Which equation is y = 9x2 + 9x – 1 rewritten in vertex form?

Anastasy [175]

Answer:

$y = 9(x +\frac{1}{2}) ^ 2 -\frac{13}{4}$

Step-by-step explanation:

An equation in the vertex form is written as

$y = a (x-h) + k$

Where the point (h, k) is the vertex of the equation.

For an equation in the form $ax ^ 2 + bx + c$ the x coordinate of the vertex is defined as

$x = -\frac{b}{2a}$

In this case we have the equation $y = 9x^2 + 9x - 1$ .

Where

$a = 9\\\\b = 9\\\\c = -1$

Then the x coordinate of the vertex is:

$x = -\frac{9}{2(9)}\\\\x = -\frac{9}{18}\\\\x = -\frac{1}{2}$

The y coordinate of the vertex is replacing the value of $x = -\frac{1}{2}$ in the function

$y = 9 (-0.5) ^ 2 + 9 (-0.5) -1\\\\y = -\frac{13}{4}$

Then the vertex is:

$(-\frac{1}{2}, -\frac{13}{4})$

Therefore The encuacion excrita in the form of vertice is:

$y = a(x +\frac{1}{2}) ^ 2 -\frac{13}{4}$

To find the coefficient a we substitute a point that belongs to the function $y = 9x^2 + 9x - 1$

The point (0, -1) belongs to the function. Thus.

$-1 = a(0 + \frac{1}{2}) ^ 2 -\frac{13}{4}$

$-1 = a(\frac{1}{4}) -\frac{13}{4}\\\\a = \frac{-1 +\frac{13}{4}}{\frac{1}{4}}\\\\a = 9$

<em>Then the written function in the form of vertice is</em>

$y = 9(x +\frac{1}{2}) ^ 2 -\frac{13}{4}$

7 0

3 years ago

What is the answer ? Please

USPshnik [31]

Answer:

1 1/18 kilograms

Step-by-step explanation:

First add 3/8 + 11/8, which equals to 11/8. Then add 5/8, which equals to 19/8. Change the improper fraction to a mixed number, and the sum is 1 1/18.

4 0

3 years ago

Read 2 more answers

If d= the number of dogs, which variable expression represents the phase below the sum of the number of dogs and the 6 cats

TEA [102]

although none of these are right, C would make the most sense

6 0

4 years ago

Read 2 more answers

The L.I.C. bulldogs won 15 soccer games last year. This year the bulldogs won 21 games. What is the percent increase in the numb

bonufazy [111]

3.5% increase
21-15=6
21/6=3.5%

8 0

3 years ago