All categories

3 years ago

When 3+4i2+i is expressed in the form a+bi, what is the value of a?

1 answer:

7 0

Multiplying and dividing with conjugate of 2+i in the given expression, we get(3+ 4i)(2-i)/(2+i)(2-i)=(6-3i+8i-4i^2)/(4-i^2)=(10+5i)/(4+1)=(10+5i)/5=2+i=a+biThus a=2

You might be interested in

6) Linear? y = 3 - 10x True False

alexgriva [62]

It’s True liner y= 3 - 10x

4 0

3 years ago

I-phones have been in such demand that their price goes up by $25 every year. If they were $430, what is the

STALIN [3.7K]

____________\______580$

3 0

1 year ago

Read 2 more answers

Points and brainly mememememe

Maksim231197 [3]

Answer:

Hello thanks for points

7 0

3 years ago

Read 2 more answers

Which expression is equivalent to this expression? thank you :)

CaHeK987 [17]

Answer:

C. -4x - 1

Step-by-step explanation:

$-\frac{1}{2}(8x+2)$

Distribute the term outside of the parenthesis, Multiply each term in the parenthesis by the term outside (do not forget to include the negative sign when multiplying);

$(-\frac{1}{2}(8x))+(-\frac{1}{2}(2))$

Simplify,

$-4x - 1$

6 0

3 years ago

| 9. The distance between Town A and Town B was 108 km. A car and a van left Town A at 12 00 for Town B. On reaching Town B, the

Westkost [7]

Answer:

a) Time until both vehicles meet is 1.5 hours after starting at noon. That makes it 1:30PM.

b) Average speed of car is 84 km/h

Step-by-step explanation:

A -----------------------z------------B

Left Speed(km/h) Time

Car: 12PM X

Van: 12PM 60

Car/Van

DistanceCar AB + z

DistanceVan Az

Ratio: (AB+z)/Az = 7/5

Time until both meet = T (in hours)

Distance Car: xT

Distance Van: 60T

====

xT = AB + z

60T = Az

---

(xT/60T)= (7/5)

x = 60(7/5)

x = 84 km/h

=====

Time for car to reach B is: time (hr) = 108 km/(84 km/h)

time = 1.286 hours

Distance for at 1.289 hours is: distance (km) = (60 km/h)*(1.286 h)

distance = 77.14 km

At 1.286 hours, the car reverses direction. The van is (108 km - 77.14 km) or 30.86 km away.

Add the distances travelled by both vehicles after the car reverses direction at 1.286 hours. The sum will be 30.86 km when they meet, at time of T.

Car Distance + Van Distance = 30.86 km

T(84 km/h) + t(60 km)

They meet when they are 0 km apart, which can be modeled with the following equation:

Van travel Distance - Car Travel Distance = 0 starting at 1.286 hr.

Let t be the time after 1.286 hours that both vehicles meet/collide.

t*(60 km/h) + t(84 km/h) = 30.86 km

t(60+84) = 30.86 km

t(144 km/h) = 30.86 km

t = 0.2143 hr

Total time until the car and van meet is 1.286 hr + 0.2143 hr for a total of 1.50 hours.

=================

a) Time until both vehicles meet is 1.5 hours after starting at noon. That makes it 1:30PM.

b) Average speed of car is 84 km/h

==============

CHECK

Is the ratio of the distance travelled by the car and the van until they meet in the ratio of 7/5?

Car distance is (1.5 hr)(84 km/h) = 126 km

Van distance is (1.5 hr)(60 km/h) = 90.0 km

Ratio is 126/90 or 1.4

Ratio of 7/5 is 1.4

YES

3 0

2 years ago