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1 year ago

If u = 2i - j; v= -5i + 4j and w = j find 4u (v -w).

Mathematics

1 answer:

Sedaia [141]1 year ago

5 0

Answer:

-40

Explanation:

Given

u = 2i - j; v= -5i + 4j and w = j

Required

4u(v-w)

4u = 4(2i) = 8i

v - w = -5i + 4j - j

v - w = -5i + 3j

Substitute

4u(v-w)

= 8i(-5i+3j)

= -40(i*i) [since i*i = 1]

= -40

Hence the required solution is -40

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Find four consecutive integers whose sum is 114.

Rzqust [24]

4 consecutive integers : (x), (x + 1), (x + 2), (x + 3)

x + x + 1 + x + 2 + x + 3 = 114...combine like terms
4x + 6 = 114....subtract 6 from both sides
4x = 114 - 6
4x = 108...divide both sides by 4
x = 108/4
x = 27

x + 1 = 27 + 1 = 28
x + 2 = 27 + 2 = 29
x + 3 = 27 + 3 = 30

so ur 4 numbers are : 27, 28, 29, 30

7 0

3 years ago

Write 6.005 in expanded form

jenyasd209 [6]

Answer:

6+0.005

Step-by-step explanation:

8 0

3 years ago

Show me how to do this

romanna [79]

Answer:

Step-by-step explanation:

The perimeter of the given triangle:

P = (2x + 1) + (x + 2) + (3x - 9) and P = 36 cm.

Therefore we have the equation:

2x + 1 + x + 2 + 3x - 9 = 36 <em>combine like terms</em>

(2x + x + 3x) + (1 + 2 - 9) = 36

6x - 6 = 36 <em>add 6 to both sides</em>

6x = 42 <em>divide both sides by 6</em>

x = 7

4 0

3 years ago

A jar contains 8 red marbles numbered 1 to 8 and 7 blue marbles numbered 1 to 7. A marble is drawn at random from the jar. Find

Shkiper50 [21]

Answer:

Therefore the probability that the marble is blue or even numbered is $\frac{11}{15}$

Step-by-step explanation:

Probability: The ratio of favorable outcomes to the total outcomes.

It is denoted by P.

$Probability= \frac{\textrm{favorable outcomes}}{\textrm{Total outcomes}}$

Given that a jar contains 8 red marbles and 7 blue marbles.

Total number of marbles = (8+7) = 15

Let A = Event of getting a blue marble

B= Event of getting of even marble.

Even number blue marbles are 2, 4,6

Even number red marbles are 2, 4,6,8

The number of even marbles are =(3+4)=7

The probability of getting a blue marble is P(A)

$=\frac{\textrm{Total number of blue marbles}}{\textrm{Total number of blue marbles}}$

$=\frac{7}{15}$

The probability of getting a even marble is P(B)

$=\frac{\textrm{The number of even number marbles}}{\textrm{Total number of marbles}}$

$=\frac{7}{15}$

The probability of getting a even numbered blue marble P(A∩B)

$=\frac{3}{16}$

P(blue marble or even- numbered)

=P(A∪B)

=P(A)+P(B)-P(A∩B)

$=\frac{7}{15} +\frac{7}{15}-\frac{3}{15}$

$=\frac{11}{15}$

Therefore the probability that the marble is blue or even numbered is $\frac{11}{15}$

3 0

3 years ago

What is the center of the circle and radius defined by the following equation?<br><br> x2+y2+4y=5

vovangra [49]

Answer:

Step-by-step explanation:

Alternate forms:

x^2 + y (y + 4) = 5

x^2 + y^2 + 4 y - 5 = 0

Solutions:

y = -sqrt(9 - x^2) - 2

y = sqrt(9 - x^2) - 2

Integer solutions:

x = ± 3, y = -2

x = 0, y = -5

x = 0, y = 1

Implicit derivatives:

(dx(y))/(dy) = -(2 + y)/x

(dy(x))/(dx) = -x/(2 + y)

7 0

3 years ago