Jawabanmu

2014-09-06T01:57:24+07:00
 5^{4x-3}+25^{3-2x} =30 \\  5^{4x-3}+5^{2(3-2x)} =30 \\  5^{4x-3}+5^{6-4x} =30 \\  5^{4x-3}+25^{(3-(4x-3))} =30 \\ 5^{4x-3}+ \frac{5^{3}}{5^{4x-3}}} =30 \\

Asumsikan 5^{4x-3} = a, maka:
 a + \frac{125}{ a}=30 \\  \frac{  a^{2}+125}{a}=30 \\    a^{2}+125=30a \\  a^{2}-30a+125=0 \\ (a-25)(a-5)=0

Maka himpunan dari a adalah a= 5 dan a=25
Untuk:
a=5 \\5^{4x-3} = 5^{1} \\ 4x-3=1 \\ x=1

a=25 \\5^{4x-3} = 5^{2} \\ 4x-3=2 \\ x= \frac{5}{4} [/tex]

Maka Hp: x=1  dan x= \frac{5}{4}
1 5 1