Math Is Fun Forum
Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °
You are not logged in.
- Topics: Active | Unanswered
#1 2006-11-20 04:37:56
- Kiran
- Member
- Registered: 2006-11-15
- Posts: 177
Next
solve for x
log4 (x - 1) + log4 (x + 2) = 1
log4 (x - 1) (x + 2) = 1
(x - 1)(x + 2) = 4^1
now what?
Live 4 Love
Offline
#2 2006-11-20 04:39:15
- Toast
- Real Member
- Registered: 2006-10-08
- Posts: 1,321
Re: Next
Well, you've done the hard part already, just solve it as a normal quadratic now. Make one side of the equation equal to zero and use factorisation and the null factor law or the quadratic formula.
Offline
#3 2006-11-20 15:35:38
- basmah
- Member
- Registered: 2006-10-02
- Posts: 18
Re: Next
yup, now just multiply and you get:
x²+2x-x-2=4
x²+x-2-4=0
x²+x-6=0
(x-2)(x+3)=0
x=2 and x=-3 are the solutions
Offline