All categories

2 years ago

HURRY!! select ALL the correct answers

Mathematics

1 answer:

Rainbow [258]2 years ago

8 0

Answer:

2nd, 3rd and 5th options are correct.

Step by step explanation:

We are asked to find which of the given operations involving complex numbers have solutions represented by point A on the graph.

We can see that point A lies on (1,-2i). Let us see which of our given expressions give us coordinates of point A.

1. $(4+i)+3(1+i)$

$4+i+3+3i$

$4+3+i+3i$

$7+4i$

We can see that our 1st option is incorrect.

2. $(4+i)-3(1+i)$

$4+i-3-3i$

$4-3-3i+i$

$1-2i$

We can see that our 2nd option is correct.

3. $(4+i)+(-3-3i)$

$4+i-3-3i$

$4-3+i-3i$

$1-2i$

We can see that our 3rd option is correct.

4. $(4+i)+(3-3i)$

$4+i+3-3i$

$4+3+i-3i$

$7-2i$

Upon simplifying our expression we got $7-2i$ which is not equal to coordinates of point A. Therefore, 4th option is incorrect.

5. $(4+i)-(3+3i)$

$4+i-3-3i$

$4-3+i-3i$

$1-2i$

Upon simplifying our expression we got coordinates of point A. Therefore, 5th option is correct indeed.

You might be interested in

Find the perimeter of shape ABCDE

EleoNora [17]

Answer:

Perimeter of a triangle = 2*(length + breadth)

SO = 2*18+41

= 77 is the perimeter

6 0

2 years ago

How do I factorise 2t^2 + 5t +2

alekssr [168]

$2t^2+5t+2\\\\a=2;\ b=5;\ c=2\\\\\Delta=b^2-4ac;\ if\ \Delta > 0\ then\ t_1=\frac{-b-\sqrt\Delta}{2a}\ and\ t_2=\frac{-b+\sqrt\Delta}{2a}\\\\\Delta=5^2-4\cdot2\cdot2=25-16=9;\ \sqrt\Delta=\sqrt9=3\\\\t_1=\frac{-5-3}{2\cdot2}=\frac{-8}{4}=-2;\ t_2=\frac{-5+3}{2\cdot2}=\frac{-2}{4}=-\frac{1}{2}\\\\2t^2+5t+2=2(x+2)(x+\frac{1}{2})$

5 0

2 years ago

QUICK QUICK PLEASE! 1 MINUTE ONLY! WITH EXPLANATION PLEASE!

Dmitriy789 [7]

Answer:

Step-by-step explanation:

<h2>first you add 60 plus 40 equals 100 then add 80 plus 50 equals 130.add 130 + 100 =230 then add 90 which is 320 next add 9 the you get 329</h2>

5 0

3 years ago

How to solve this question

VMariaS [17]

<span>The variance method is as follows.

-Sum the squares of the values in data set, and then divide by the number of values in data set
- From that, subtract the square of the mean (add all values and divide by number of values in the data set)

Our variance is

<span> $\displaystyle\sigma^2 = \frac{2^2 + 5^2 + m^2}{3} - \left(\frac{2 + 5 + m}{3}\right)^2$

Since variance has to be 14, we set $\sigma^2 = 14$ and solve for m

$14= \frac{4 + 25 + m^2}{3} - \left(\frac{7 + m}{3}\right)^2\ \Rightarrow \\ \\
14 = \frac{29}{3} + \frac{1}{3}m^2 - \frac{1}{9}(7+m)^2 \\ \\
14 = \frac{29}{3}+ \frac{1}{3}m^2 - \frac{1}{9}(49 + 14m + m^2) \\ \\
14 = \frac{29}{3}+ \frac{1}{3}m^2 - \frac{49}{9}- \frac{14}{9}m- \frac{1}{9}m^2 \\ \\
0 = \frac{-88}{9} -\frac{14}{9}m + \frac{2}{9}m^2
$

quadratic formula

$m = \displaystyle\frac{-b \pm \sqrt{b^2 -4ac}}{2a} \\
m = \frac{-(-\frac{14}{9}) \pm \sqrt{\left(-\frac{14}{9}\right)^2 - 4(2/9)(-88/9)} }{2(2/9)} \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{196}{81} + \frac{704}{81} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{900}{81} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{100}{9} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \frac{10}{3} }{\frac{4}{9} } \\
m = 11, -4$

-4 doesnt' work as it is not a positive integer

m = 11

</span></span>

5 0

2 years ago

Krutika was thinking of a number. Krutika adds 4 to it, then doubles it and gets an answer of 83.9. What was the original number

mr Goodwill [35]

Answer:37.95

Step-by-step explanation:

8 0

2 years ago