Item 2

7th grade math pls help

KengaRu [80]

Answer:

B

Step-by-step explanation:

8 0

3 years ago

Use Euler's method with step size 0.2 to estimate y(1), where y(x) is the solution of the initial-value problem y' = x2y − 1 2 y

irina [24]

Answer:

Therefore the value of y(1)= 0.9152.

Step-by-step explanation:

According to the Euler's method

y(x+h)≈ y(x) + hy'(x) ....(1)

Given that y(0) =3 and step size (h) = 0.2.

$y'(x)= x^2y(x)-\frac12y^2(x)$

Putting the value of y'(x) in equation (1)

$y(x+h)\approx y(x) +h(x^2y(x)-\frac12y^2(x))$

Substituting x =0 and h= 0.2

$y(0+0.2)\approx y(0)+0.2[0\times y(0)-\frac12 (y(0))^2]$

$\Rightarrow y(0.2)\approx 3+0.2[-\frac12 \times3]$ [∵ y(0) =3 ]

$\Rightarrow y(0.2)\approx 2.7$

Substituting x =0.2 and h= 0.2

$y(0.2+0.2)\approx y(0.2)+0.2[(0.2)^2\times y(0.2)-\frac12 (y(0.2))^2]$

$\Rightarrow y(0.4)\approx 2.7+0.2[(0.2)^2\times 2.7- \frac12(2.7)^2]$

$\Rightarrow y(0.4)\approx 1.9926$

Substituting x =0.4 and h= 0.2

$y(0.4+0.2)\approx y(0.4)+0.2[(0.4)^2\times y(0.4)-\frac12 (y(0.4))^2]$

$\Rightarrow y(0.6)\approx 1.9926+0.2[(0.4)^2\times 1.9926- \frac12(1.9926)^2]$

$\Rightarrow y(0.6)\approx 1.6593$

Substituting x =0.6 and h= 0.2

$y(0.6+0.2)\approx y(0.6)+0.2[(0.6)^2\times y(0.6)-\frac12 (y(0.6))^2]$

$\Rightarrow y(0.8)\approx 1.6593+0.2[(0.6)^2\times 1.6593- \frac12(1.6593)^2]$

$\Rightarrow y(0.6)\approx 0.8800$

Substituting x =0.8 and h= 0.2

$y(0.8+0.2)\approx y(0.8)+0.2[(0.8)^2\times y(0.8)-\frac12 (y(0.8))^2]$

$\Rightarrow y(1.0)\approx 0.8800+0.2[(0.8)^2\times 0.8800- \frac12(0.8800)^2]$

$\Rightarrow y(1.0)\approx 0.9152$

Therefore the value of y(1)= 0.9152.

4 0

3 years ago

The Earth has a mass of about 6 x 10^24 kg. Neptune has a mass of 1.8 x 10^27kg. How many times bigger is Neptune than Earth

elena-s [515]

Answer:

300 times bigger.

Step-by-step explanation:

That would be (1.8 * 10^27 ) / (6 * 10^24)

= 0.3 * (10^27/10^24)

= 0.3 * 10^3

= 3 * 10^2

= 300.

5 0

3 years ago

What expressions equal to 1 forth of 52

Klio2033 [76]

Remember that x/4 and 1/4*x is the same thing.

1/4*52 is therefore the same as 52/4. Fractions represent division, so 52 divided by 4 is also correct.
0.25*x is the same as 1/4*x because 1/4=0.25
4% of 52 is incorrect because the decimal form of 4% is 0.04, which is not the same as 0.25

Final answer: B

5 0

4 years ago

Read 2 more answers

which equation represents a line that is parallel to the line whose equation is 3x-2y=7; which equation represents a line parall

aleksley [76]

The equation of the line that is parallel to the line whose equation is 3x-2y=7 would be y = 3/2x + b, in which b can be any real number.

How are parallel straight lines related?

Parallel lines have the same slope since the slope is like a measure of steepness and since parallel lines are of the same steepness, thus, are of the same slope.

We have been given a parallel line with has equation

3x-2y=7

In order to solve this, the slope of the original line.

3x - 2y = 7

-2y = -3x + 7

y = 3/2x - 7/2

thus its slope is 3/2.

thus, the slope of the needed line is 3/2 too.

we know that any line that is parallel to that would have this slope.

So anything is written in the form:

y = 3/2x + b

The equation of the line that is parallel to the line whose equation is 3x-2y=7 would be y = 3/2x + b, in which b can be any real number.

Learn more about parallel lines here:

brainly.com/question/13857011

#SPJ4

3 0

1 year ago