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Wave Equation : D'Alembert's Solution

Given that the general solution to the wave equation in one space dimension is given by where f, g are arbitrary twice continuously differentiable functions deduce that the solution s satisfying the initial conditions and for some function v, is (this is a special case of the so called D'Alembert's solution of


Evaluate the integers. Please see attached.

Volume of a Solid of Revolution (2 Problems)

Find the volume of the solid obtained by rotating the region bounded by the given curve about the specific line. (a) y=e^{5x}, y=0, x=0, x=1, about x -axis (b) x=5y-y^2, x=0, about y -axis"

Average Temperature from a Function

In a certain city the temperature at t hours after 9 A.M. is approximated by the function T(t)=44+12sin(pi(t))/12). What is the average temperature of the city during the period from 9 A.M. to 9 P.M.?

Area of a Region Between Two Curves

Consider the region enclosed by the curves 2y=4sqrt{x}, y=5, 2y+4x=8. [Note: the y-axis is not a boundary of this region.] Decide whether to integrate with respect to x or y. What is the area of the region?

Solve Sequences Used in Given Situation

There is a rope that stretches from the top of Maidwell building to a tree on the racecourse, and the length of this rope is 1km. A worm begins to travel along the rope at the rate of 1cm each second in an attempt to get to the other end. then a strange thing happens... some malevolent deity intervenes to make life even hard

Evaluating integrals

Evaluate the following integrals: (1)The integral of (6sin[2x])/sin(x)dx=____+C (2)The integral of (7-x)(3+[x^2])dx=____+C (3)The integral from 3 to 7 of ([t^6]-[t^2])/(t^4)dt=____+C (4)The integral of (6sin[x])/(1-sin^2[x])dx=____+C

Definite and indefinite integrals

Thank you in advance for your help. Evaluate the following definite and indefinite integrals: (1)The integral of (2x)/([x^2]+1)dx (2)The integral of [(arctan(x))/([x^2]+1)]dx (3)The integral of sqrt([x^3]+[1x^5])dx (4)The integral of (2+x)/([x^2]+1)dx (5)The integral of (2x)/([x^4]+1)dx (6)The integral from 0 to 2 of (x

Evaluating Integrals via Substitution

Thank you in advance for your help. Evaluate the integrals by making the given substitution: (a)The integral of x(4+x^2)^3dx; (u=4+x^2) (b)The integral of ((sin sqrt[x])/sqrt[3x])dx; (u=sqrt[x]) (c)The integral of e^(3sin(t))cos(t)dt; (u=sin(t))

Indefinite integrals

Thank you in advance for your help. Find the general indefinite integrals: (a)The integral of x(1+2x^2)dx (b)The integral of ((x^2)+1+(2/x^2+1))dx

Integrals : Rate of Change Word Problem

Water flows from the bottom of a storage tank at a rate of r(t)=200-4t liters per minute, where 0 is less than or equal to t and t is less than or equal to 50. Find the amount of water that flows from the tank during the first 10 minutes.


Consider the definite integral I 4 I = ∫ e^x dx 0 1. evaluate the integral I directly by use of a suitable anti-derivative. 2. evaluate the integral I by use of a suitable Riemann sum and formally limiting that sum 3. evaluate the integral I by use of the trapezoidal rule: a) I T,2 - for 2

Deriving an integration rule

Derive an integration rule for the domain [0,1] based on the quadrature points x1=0, x2=1/3 and x3=1, which is exact for polynomials of degree <= 2. Please see attached for full question.

Integral of a Contour

Calculate the following integrals: &#8747; from 0 to &#8734; x^¼/(x²+9) dx Please see attached for proper format.

Integral of Continuous Decreasing Function on a Closed Interval

Suppose f(x) is continuous and decreasing on the closed interval (4 is less than or equal to x is less than or equal to 11), that f(4)=6, f(11)=3, and that the integral as 4 goes to 11 of f(x)dx=27.01678. What is the integral as 3 goes to 6 of f^-1(x)dx?

Properties of Integrals : Verify an Inequality

Use the properties of integrals to verify the inequality without evaluating the integral: [the integral as 1 goes to 2 of (sqrt(5-x))dx] is greater than or equal to [the integral as 1 goes to 2 of (sqrt(x+1))dx].

Integrals : Riemann Sum with Diagrams

This question has me going around in circles. I can't make the Sigma symbol on the computer, so I used the word "Sigma" instead. For (c), n is above the Sigma symbol and i=1 is below it. (a)Find an approximation to the integral as 0 goes to 4 of (x^2-3x)dx using a Riemann sum with right endpoints and n=8. (b)Draw a diagram

Elementary Numerical Analysis

GAUSSIAN NUMERICAL INTEGRATION 1. Consider approximating integrals of the form... in which f(x) has several continuous derivatives on [0, 1] a. Find a formula... which is exact if f(x) is any linear polynomial. b. To find a formula... which is exact for all polynomial of degree &#8804; 3, set up a system of four e