Express the set of real numbers between but not including 2 and 5 as follows.

LUCKY_DIMON [66]

4500 = 4.5 * 10^3

57 = 5.7 * 10^1

730 = 7.3 * 10^2

0.007 = 7 * 10^-3

300.25 = 3.0025 * 10^2

56,325.2 = 5.63252 * 10^4

3 0

3 years ago

Read 2 more answers

Suppose that \nabla f(x,y,z) = 2xyze^{x^2}\mathbf{i} + ze^{x^2}\mathbf{j} + ye^{x^2}\mathbf{k}. if f(0,0,0) = 2, find f(1,1,1).

lesya [120]

The simplest path from (0, 0, 0) to (1, 1, 1) is a straight line, denoted $C$ , which we can parameterize by the vector-valued function,

$\mathbf r(t)=(1-t)(\mathbf i+\mathbf j+\mathbf k)$

for $0\le t\le1$ , which has differential

$\mathrm d\mathbf r=-(\mathbf i+\mathbf j+\mathbf k)\,\mathrm dt$

Then with $x(t)=y(t)=z(t)=1-t$ , we have

$\displaystyle\int_{\mathcal C}\nabla f(x,y,z)\cdot\mathrm d\mathbf r=\int_{t=0}^{t=1}\nabla f(x(t),y(t),z(t))\cdot\mathrm d\mathbf r$

$=\displaystyle\int_{t=0}^{t=1}\left(2(1-t)^3e^{(1-t)^2}\,\mathbf i+(1-t)e^{(1-t)^2}\,\mathbf j+(1-t)e^{(1-t)^2}\,\mathbf k\right)\cdot-(\mathbf i+\mathbf j+\mathbf k)\,\mathrm dt$

$\displaystyle=-2\int_{t=0}^{t=1}e^{(1-t)^2}(1-t)(t^2-2t+2)\,\mathrm dt$

Complete the square in the quadratic term of the integrand: $t^2-2t+2=(t-1)^2+1=(1-t)^2+1$ , then in the integral we substitute $u=1-t$ :

$\displaystyle=-2\int_{t=0}^{t=1}e^{(1-t)^2}(1-t)((1-t)^2+1)\,\mathrm dt$

$\displaystyle=-2\int_{u=0}^{u=1}e^{u^2}u(u^2+1)\,\mathrm du$

Make another substitution of $v=u^2$ :

$\displaystyle=-\int_{v=0}^{v=1}e^v(v+1)\,\mathrm dv$

Integrate by parts, taking

$r=v+1\implies\mathrm dr=\mathrm dv$

$\mathrm ds=e^v\,\mathrm dv\implies s=e^v$

$\displaystyle=-e^v(v+1)\bigg|_{v=0}^{v=1}+\int_{v=0}^{v=1}e^v\,\mathrm dv$

$\displaystyle=-(2e-1)+(e-1)=-e$

So, we have by the fundamental theorem of calculus that

$\displaystyle\int_C\nabla f(x,y,z)\cdot\mathrm d\mathbf r=f(1,1,1)-f(0,0,0)$

$\implies-e=f(1,1,1)-2$

$\implies f(1,1,1)=2-e$

3 0

3 years ago

A cab company charges a flat fee of $5.00 and then an additional $0.45 per mile. Write an equation expressing the cost of a ride

Oliga [24]

The equation representing the cost of the ride is R = $5 + $0.45dd.

The flat fee charged is the fixed cost. This cost remains constant regardless of the distance travelled. The additional fee is the variable cost. It increases with the distance travelled.

<h3> Derivation of the equation that represents cost of the ride.</h3>

Total cost = fixed cost + (variable cost x miles driven)

R = $5 + $0.45dd

To learn more about flat fees, please check: brainly.com/question/25879561

6 0

3 years ago

Use the table in the previous question where 5 peppers cost $2.25 to answer the below.

Ronch [10]

If five peppers cost $2.25 then you could buy 40 peppers with $18 dollars and have $2 left over

3 0

3 years ago

Read 2 more answers