Questions
Differential equation

Solve the differential equation with details explaination :

x²y" + 6xy' - 24y=x^9

In: Advanced Math

Kernal ( Homomorphisms)

Prove that φ : Z ⊕ Z → Z by φ(a, b) = a − b is a homomorphism. Determine the kernel.

In: Advanced Math

Homomorphisms

How many (group) homomorphisms are there from Z20 onto (surjective to) Z8. How many are there to Z8?

In: Advanced Math

Gaussian Elimination

Solve using Gaussian elimination with partial pivoting and 4 digit arithematic

In: Advanced Math

Maclaurin Series

Find the Maclaurin Series of the following functions:

(a) f(x)= Ln(3+x)

(b) f(x)= cos(3x)

(c) f(x) = x^(2)(e^(-x))

In: Advanced Math

Mathematical modeling

A population of squirrels living in a forest with a carrying capacity of 2600.(assume logistics growth with constant k=0.9yr)

(a)find a formula for the squirrels population p(t) assuming an initial population of 650 squirrels.

(b)how long will it take for the squirrels population to double?

In: Advanced Math

Mathematical modeling

A population of squirrels living in a forest with a carrying capacity of 2600.(assume logistics growth with constant k=0.9yr)

(a)find a formula for the squirrels population p(t) assuming an initial population of 650 squirrels.

(b)how long will it take for the squirrels population to double?

In: Advanced Math

Methods 1

Find two linearly independent solution of 

y"+7xy=0.  of the form

y1=1+a3x^3+a6x^6+....

y2=x+b4x^4+b7x^7+....

Enter the first few co-efficients

a3=

a6=

b4=

b7=

In: Advanced Math

Optimization Problem

We want to construct a box whose base length is three times the base width. The material used to build the top and bottom cost $10/ft2 and the material to build the sides cost $6/ft2 . If the box must have volume 50 ft3 , what is the minimum cost of the box?

In: Advanced Math

Prove the formulas given in this table for the derivatives of the functions cosh, tanh, csch, sech, and coth.

Prove the formulas given in this table for the derivatives of the functions cosh, tanh, csch, sech, and coth. Which of the following are proven correctly? (Select all that apply.)

\(\square \frac{d}{d x}(\operatorname{coth} x)=\frac{d}{d x}\left(\frac{\sinh x}{\cosh x}\right)=\frac{\cosh x \cosh x-\sinh x \sinh x}{\cosh ^{2} x}=\frac{\cosh ^{2} x-\sinh ^{2} x}{\cosh ^{2} x}=-\frac{1}{\cosh ^{2} x}=-\operatorname{csch}^{2} x\) \(\square \frac{d}{d x}(\operatorname{csch} x)=\frac{d}{d x}\left(\frac{1}{\sinh x}\right)=-\frac{\cosh x}{\sinh ^{2} x}=-\frac{1}{\sinh x} \cdot \frac{\cosh x}{\sinh x}=-\operatorname{csch} x \operatorname{coth} x\)

\(\square \frac{d}{d x}(\cosh x)=\frac{d}{d x}\left[\frac{1}{2}\left(e^{x}-e^{-x}\right)\right]=\frac{1}{2}\left(e^{x}+e^{-x}\right)=\sinh x\)

\(\square \frac{d}{d x}(\operatorname{csch} x)=\frac{d}{d x}\left(\frac{1}{\sinh x}\right)=-\frac{\cosh ^{2} x}{\sinh ^{2} x}=-\frac{1}{\sinh x} \cdot \frac{\cosh ^{2} x}{\sinh x}=-\operatorname{csch} x \operatorname{coth} x\)

\(\square \frac{d}{d x}(\operatorname{sech} x)=\frac{d}{d x}\left(\frac{1}{\cosh x}\right)=-\frac{\sinh x}{\cosh ^{2} x}=-\frac{1}{\cosh x} \cdot \frac{\sinh x}{\cosh x}=-\operatorname{sech} x \tanh x\)

In: Advanced Math

Find dy/dx and d2 y/dx2 . For which values of t is the curve concave upward? 13. x = et , y = te-t

Find dy/dx and d2 y/dx. For which values of t is the curve concave upward?

13. x = et , y = te-t

In: Advanced Math

Find the equation of the plane through the point (1,1,1) which is perpendicular to the line of intersection of the two planes x−y−3z=−1 and x−3y+z= 2.

Find the equation of the plane through the point (1,1,1) which is perpendicular to the line of intersection of the two planes x−y−3z=−1  and x−3y+z= 2.

In: Advanced Math

Solve the 4 degree polynomial equation.

Solve the 4 degree polynomial equation \( x^4 − 2x^3 + 4x^2+ 6x − 21 = 0 \), given that the sum of two its roots is zero.

In: Advanced Math