In rectangle MATH, AT = 8 and TH = 12. Find the length of

Use the Trapezoidal Rule, the Midpoint Rule, and Simpson's Rule to approximate the given integral with the specified value of n.

Vera_Pavlovna [14]

Split up the integration interval into 4 subintervals:

$\left[0,\dfrac\pi8\right],\left[\dfrac\pi8,\dfrac\pi4\right],\left[\dfrac\pi4,\dfrac{3\pi}8\right],\left[\dfrac{3\pi}8,\dfrac\pi2\right]$

The left and right endpoints of the $i$ -th subinterval, respectively, are

$\ell_i=\dfrac{i-1}4\left(\dfrac\pi2-0\right)=\dfrac{(i-1)\pi}8$

$r_i=\dfrac i4\left(\dfrac\pi2-0\right)=\dfrac{i\pi}8$

for $1\le i\le4$ , and the respective midpoints are

$m_i=\dfrac{\ell_i+r_i}2=\dfrac{(2i-1)\pi}8$

Trapezoidal rule

We approximate the (signed) area under the curve over each subinterval by

$T_i=\dfrac{f(\ell_i)+f(r_i)}2(\ell_i-r_i)$

so that

$\displaystyle\int_0^{\pi/2}\frac3{1+\cos x}\,\mathrm dx\approx\sum_{i=1}^4T_i\approx\boxed{3.038078}$

Midpoint rule

We approximate the area for each subinterval by

$M_i=f(m_i)(\ell_i-r_i)$

so that

$\displaystyle\int_0^{\pi/2}\frac3{1+\cos x}\,\mathrm dx\approx\sum_{i=1}^4M_i\approx\boxed{2.981137}$

Simpson's rule

We first interpolate the integrand over each subinterval by a quadratic polynomial $p_i(x)$ , where

$p_i(x)=f(\ell_i)\dfrac{(x-m_i)(x-r_i)}{(\ell_i-m_i)(\ell_i-r_i)}+f(m)\dfrac{(x-\ell_i)(x-r_i)}{(m_i-\ell_i)(m_i-r_i)}+f(r_i)\dfrac{(x-\ell_i)(x-m_i)}{(r_i-\ell_i)(r_i-m_i)}$

so that

$\displaystyle\int_0^{\pi/2}\frac3{1+\cos x}\,\mathrm dx\approx\sum_{i=1}^4\int_{\ell_i}^{r_i}p_i(x)\,\mathrm dx$

It so happens that the integral of $p_i(x)$ reduces nicely to the form you're probably more familiar with,

$S_i=\displaystyle\int_{\ell_i}^{r_i}p_i(x)\,\mathrm dx=\frac{r_i-\ell_i}6(f(\ell_i)+4f(m_i)+f(r_i))$

Then the integral is approximately

$\displaystyle\int_0^{\pi/2}\frac3{1+\cos x}\,\mathrm dx\approx\sum_{i=1}^4S_i\approx\boxed{3.000117}$

Compare these to the actual value of the integral, 3. I've included plots of the approximations below.

3 0

3 years ago

90 hazelnuts have a mass of 125 g. Hazelnuts have 630 calories per 100 g. work out the number of calories per hazelnut

jenyasd209 [6]

90 hazelnuts = 125g

Therefore, the mass of one hazelnut is this...

90 / 90 = 125 / 90

1 hazelnut = 25/18 grams

630 calories = 100 grams

100 divided by 25/18 = 72

Therefore...

630 / 72 = 1 hazelnut

AND THE ANSWER IS

8.75 calories = 1 hazelnut

8 0

3 years ago

Read 2 more answers

Children who have lost some baby teeth have better arithmetic skills than children who have not lost any baby teeth. In fact, th

Tems11 [23]

Answer:

B. There is correlation but no direct casual relation, but losing teeth and arithmetic skills.

Step-by-step explanation:

Given:

Correlation between lost of baby teeth and arithmetic skills.

Solution:

Correlation and causality concepts are so used here.

Correlation is the relationship between two variables to get or to predict information.

Correlation is not always causation.

So here the correlation is used to predict the arithmetic skills based on lost teeth.

i.e. More teeth lost more arithmetic skills.

Causality means change in one variable changes value of other variable.

So it gives direct causal relation between the variables.

Here they given relationship between the children lost teeth and arithmetic skills to predict information.

But ,there no actual imply on correlation.

Arithmetic skills can also depends upon third variable.

Hence there is no direct causal relationship between them.

8 0

3 years ago

The table below shows the numbers of tickets sold at a movie theater on Friday.

kondor19780726 [428]

Answer:

Number of Adult's tickets sold on Saturday = 3,356

Number of Children's tickets sold on Saturday = 2, 928

Total number of tickets sold over these two days is 8,938.

Step-by-step explanation:

Here, the number of tickets sold on FRIDAY:

Adult Ticket sold = 1,678

Children's Tickets sold = 976

So, the total number of tickets sold on Friday

= Sum of ( Adult + Children's ) tickets = 1,678 + 976 = 2,654 .... (1)

The number of tickets sold on SATURDAY:

Adult Ticket sold = 2 times the number of adult tickets sold on Friday

= 1,678 x 2 = 3,356

Children's Tickets sold = 3 times the number of children's tickets sold on Friday.

= 976 x 3 = 2, 928

So, the total number of tickets sold on Saturday

= Sum of ( Adult + Children's ) tickets = 3,356 + 2,928 = 6, 284 .... (2)

Now, the total number of tickets booked in these two days :

Sum of tickets booked on (Friday + Saturday)

= 2,654 + 6, 284 = 8,938

Hence, total number of tickets sold over these two days is 8,938.

6 0

3 years ago

How much will a $1.42 loaf of bread cost in 25 years based on inflation

Setler [38]

It will cost $17.60 in 25 years based on inflation

4 0

3 years ago