Datrys 5^n-1=25

$$5 ^ { n - 1 } = 25$$

Datrys ar gyfer n

$$n=3$$

Camau gan Ddefnyddio Diffiniad Logarithm

Defnyddio rheolau esbonyddion a logarithmau i ddatrys yr hafaliad.

$$5^{n-1}=25$$

Cymryd logarithm dwy ochr yr hafaliad.

$$\log(5^{n-1})=\log(25)$$

Logarithm rhif wedi’i godi i bŵer yw’r pŵer wedi’i lluosi â logarithm y rhif.

$$\left(n-1\right)\log(5)=\log(25)$$

Rhannu’r ddwy ochr â \log(5).

$$n-1=\frac{\log(25)}{\log(5)}$$

Gyda’r fformiwla newid-sail \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).

$$n-1=\log_{5}\left(25\right)$$

Adio 1 at ddwy ochr yr hafaliad.

$$n=2-\left(-1\right)$$