Wednesday

September 17, 2014

September 17, 2014

Posted by **Sara** on Sunday, January 15, 2012 at 1:19pm.

e^x-42e^-x= -19

- precalculus -
**Reiny**, Sunday, January 15, 2012 at 4:39pmmultiply each term by e^x

(e^x)^2 - 42 + 19e^x = 0

let y = e^x

y^2 + 19y - 42 = 0

(y+21)(y-2) = 0

y = -21 or y = 2

so e^x = 2

x = ln 2

or

e^x = -21, which has no solution

x = ln2

- precalculus -
**Sara**, Sunday, January 15, 2012 at 5:46pmthanks again

**Answer this Question**

**Related Questions**

precalculus - solve the exponential equation express in exact form only show all...

algebra - solve the exponential equation Express in exact form. 5e^xlog_9 = 11 ...

Math - Exponential equation - Solve the exponential equation. Express your ...

precalculus - Solve the logarithmic equation. Express your solutions in exact ...

pre calculus - Solve the exponential equation Express you solutions in exact ...

calculus - Having a really hard time with this! e^8x^2-5 = 14 solve the ...

college algebra - Solve the exponential equation. Express your solutions in ...

Math - 2 - Solve the exponential equation. Express your solutions in exact form ...

precalculus - solve the logarithmic equation . express solution in exact form ...

exponential equation-Algebra - Solve the exponential equation. Express the ...