løse dette log likningen??
3^2x-3=60
blir det?
2x-3=20
x=11,5
matte hjelp
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Dolandyret
- Lagrange
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- Joined: 04/10-2015 22:21
er det [tex]3^{2x}-3=60[/tex] eller [tex]3^{2x-3}=60[/tex] ?vgshjelpmatte wrote:løse dette log likningen??
3^2x-3=60
blir det?
2x-3=20
x=11,5
"I want to die peacefully in my sleep like my grandfather, not screaming in terror like his passengers."
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Dolandyret
- Lagrange
- Posts: 1264
- Joined: 04/10-2015 22:21
ta logaritmen på begge sider og flytt ned eksponenten. Så bruker du bare vanlige likningsregler.vgshjelpmatte wrote:nr 2
"I want to die peacefully in my sleep like my grandfather, not screaming in terror like his passengers."
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Dolandyret
- Lagrange
- Posts: 1264
- Joined: 04/10-2015 22:21
[tex]lg3^{2x-3}=lg60[/tex]vgshjelpmatte wrote:blir det da
lg3^(2x-3)=lg60
2x-3=60
x=11,5
??? er det rett
[tex]2x-3=\frac{lg60}{lg3}[/tex]
[tex]x=\frac{\frac{lg60}{lg3}+3}{2}[/tex]
[tex]x\approx 3.36[/tex]
"I want to die peacefully in my sleep like my grandfather, not screaming in terror like his passengers."