Explore BrainMass
Share

# Calculus and Analysis

### Integral Equation Solved

Please show me how to solve this equation - can it be solved by substitution or am I on the wrong track? *(Please see attachment for equation)

### Y as a function of x

Find y as a function of x if: (x^2)(y'') + 15xy'+49y = 0 y(1) = -4 y'(1) = -3

### Instantaneous rate of change: Pool problem

A swimming pool is 20 ft wide, 40 ft long, 3 ft deep at the shallow end, and 9 ft deep at its deepest point. If the pool is being filled at a rate of 0.8 ft^3/min, how fast is the water level rising when the depth at the deepest point is 5 ft?

### Rate of change

A water trough is 10 m long and a cross-section has the shape of an isosceles trapezoid that is 30 cm wide at the bottom, 80 cm wide at the top, and has height 50 cm. If the trough is being filled with water at a rate of 0.2 m^3/min, how fast is the water level rising when the water is 30 cm deep?

### Instantaneous Rate of Change of Water

A trough is 10 ft long and its ends have the shape of isosceles triangles that are 3 ft across at the top and have a height of 1 ft. If the trough is being filled with water at a rate of 12 ft^3/min, how fast is the water level rising when the water is 6 inches deep?

### Calculus and Analysis: Functions

See attached for details.

### Function and Differential Equations

Please assist me with the attached problems relating to functions and (partial) differential equations. Thanks very much. Please tell me which is true and which is false. Then please explain why it is true or false. As you see c, d, and e are the answers I believe and next to some in parenthesis are some basic explanations.

### Second order linear diff. equation

Find y as function of t if 64y'' + 64y' +18y = 0 y(0)=4 y'(0)=4 in terms of sine and cosine

### 2nd order ODE

64y'' + 64y' +18y = 0 y(0)=4 y'(0)=4 find y as a function of t

### Second Order Differential Equation: Key Information

Y'' + 10y' + 106y = 0 y(0)=2 y'(0) = 6 Find y as a function of t .

### Second order differential equation

Find y as function of t if 49y'' - 14y' +y =0 y(0)=3 y'(0)=9 simplify to sine and consines

### Second order differential equation

4y'' + 30y=0 find y as a function of t y(0)=5 y'(0)=7

### Solve: Second Order Linear Differential Equation

Find y as a function of t in y''- y = 0 y(0)=9 y(1)=2 Make sure to show all work required for solving.

### Solving: Second Order Differential Equation

Please solve the following question: Find y as a function of t if: 25y'' +81y=0 y(0)=3 y'(0)=6 Show all work.

### Recursion relation of the Hermite polynomial

Show that for a Hermite polynomial H(n) of order n, we have: H(n+1)-xH(n)+nH(n-1)=0

### The Equation of a Tangent

Differential Calculus The Equation of a Tangent

### Multivariable Calculus: Fastest Decreasing Function

Question 1) Find the direction from (-3, 1, 2), in which g(x,y,z)=x^2*y*z-2*z^3 decreases fastest. question 2) Follow the line in the direction you found in part 1) to estimate, using linear approximation, the location of the point closest to the coordinates (-3,1,2) at which g=1;Do not use a calculator; Express the answer us

### Multivariable Calculus: Partial Derivative

Let x = (1/2)(u^2-v^2), y=uv, and f=f(x,y) [QUESTION 1] use the chain rule to derive the change of variables formula in matrix form: (fu,fv)=A*(fx,fy) {actually it is vertical , so fu is at the top and fv is at the bottom. Same for fx and fy: fx is under fy; sorry for the notation I cant do it another way} [QUESTION 2]

### Multivariable calculus

Consider the function : f(x,y) = x(x-1)(x-2) + (y-1)(x-y) [QUESTION 1]find the maximum and the minim values of the directional derivative (df/ds)]u at ( 1 , 3/2 ) as u varies . ( (df/fs)]u : I can't write the symbol clearly but it means : the derivative of f according to s on the directi

### Multivariable calculus

Consider a triangle in the plane, with angles , a, b , c. Assume that the radius of its circle is equal to 1. 1) by decomposing the triangle into six right triangles having the incenter as a common vertex, express the area A of the triangle in term of a, b , c ( the answer should be a symmetric expression). Then use the resu

### Important information about Logistic model

A population obeys the logistic model. It satisfies the equation dP/dt = 2/1300 P(13-P) for P>0 Assume P(0)= 3 Find P(74)

### Explicit/implicit solutions

Find an explicit or implicit solutions to the differential equation: (x^2 + 4xy)dx + xdy = 0 "F(x,y) such that the solutions are F(x,y)=c for an arbitrary constant c".

### Exact Curve Equations

The following differential equation is exact. Find a function F(x,y) whose level curves are solutions to the differential equation: ydy-xdx=0 "F(x,y) such that the solutions are F(x,y)=c for an arbitrary constant c".

The steady state deflection is given by: y''''+c^4*y=f(x) calculate and plot the deflection for a load: f = 1 for |x|<10, f=0 everywhere else. using Fourier transform. Plot the deflection for various values of c.

### Limits Indicated Functions

Limit f(x) (x to 1) and limit f(x) (x to -1), where f(x) = 1/x-1 if x < -1 x^2 + 2x if x is greater than or equal to -1

### Surface area as a function of box length

A closed box with a square base is to have a volume of 1,500 cubic inches. Express its surface area as a function of the length of its base.

### Write an equation of the line

Write an equation for the line with the given properties Through (2.5) and parallel to the y axis.

### Finding Slope and Intercepts

Find the slope and intercepts of the given line and draw a graph. X+3/-5 + y-1/2 = 1

### Find the points of interesection (if any) of the given pair of curves and draw the graphs.

2x-3y = -8 and 3x-5y = -13

### finding the domain of a function

H(u)= ^4 to the square root of u^2-4