# Solve System of Equations

• Apr 9th 2014, 04:54 AM
nycmath
Solve System of Equations
Solve this system of equations.

y = x^(3/2)
y = e^(-x)

My Answer is x = e^(-2x/3).
Is this right?
• Apr 9th 2014, 05:23 AM
romsek
Re: Solve System of Equations
Quote:

Originally Posted by nycmath
Solve this system of equations.

y = x^(3/2)
y = e^(-x)

My Answer is x = e^(-2x/3).
Is this right?

Nah. The solution to this system is in terms of the Lambert W function which I'd be surprised if you've been taught about.

Lambert W function - Wikipedia, the free encyclopedia

$x=\dfrac 3 2 W(\frac 2 3)$

You sure you have the problem correctly written?
• Apr 22nd 2014, 01:26 PM
HallsofIvy
Re: Solve System of Equations
Quote:

Originally Posted by nycmath
Solve this system of equations.

y = x^(3/2)
y = e^(-x)

My Answer is x = e^(-2x/3).
Is this right?

Far from being the "right answer", it is not even an "answer"! You must have x= a single number. No matter how complicated the right side there cannot be an "x" on the right side.
• Apr 22nd 2014, 06:08 PM
Prove It
Re: Solve System of Equations
Quote:

Originally Posted by nycmath
Solve this system of equations.

y = x^(3/2)
y = e^(-x)

My Answer is x = e^(-2x/3).
Is this right?

Part of your answer will be the values of x which satisfy this equation. The only way to do that (unless you know the Lambert W Function) is using numerical methods or getting a decimal approximation with a calculator (which also uses numerical methods).

You then need to get the corresponding y values.