Thursday

November 27, 2014

November 27, 2014

Posted by **Matt** on Saturday, January 12, 2008 at 1:22pm.

For which values of r does the function defined by y=e^(rt) satisfy the differential equation y''+ y'-6y = 0

- Calculus -
**bobpursley**, Saturday, January 12, 2008 at 1:43pmfind y', and y"

y'=r y

y"=r^2 y

now put them in the equation...

and divide both sides by y (y cann never be zero).

now solve for r.

r^2+r-6=0

- Calculus -
**Matt**, Saturday, January 12, 2008 at 2:28pmhow did you get ry and r^2y for y' and y''?

- Calculus -
**Damon**, Saturday, January 12, 2008 at 4:01pmif y = e^rt where r is constant and t is variable

then

dy/dt = r e^rt

since e^rt = y then

dy/dt = r y

d/dy(dy/dt) = d^2y/dt^2 = r*re^rt

= r^2 e^rt

= r^2 y again since y = e^rt

**Answer this Question**

**Related Questions**

Another Calculus - Sorry I have been trying to figure this out all day. Find the...

Calculus - Hi! My question is: Given that f is a function defined by f(x) = (2x...

Calculus - A cubic polynomial function f is defined by f(x) = 4x^3 + ax^2 + bx...

Calculus - A cubic polynomial function f is defined by f(x) = 4x^3 + ax^2 + bx...

English - I need help with this homework: Present Perfect vs Present Perfect ...

Math - Consider the function y=sqrt(1+cos2x)/2 (everything is under the square ...

Medical coding - Please indicate all ICD-9 diagnosis and procedure codes for the...

Grammar - I'm still really confused with this one; I posted it up a couple of ...

calculus - i'm having trouble with a problem in my calc class...it isn't really ...

Site not working correctly/Physics - I posted a question a couple of days ago ...