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4 votes
(1/4)^3z-1 =16^z+2*64^z-2

Z=___

Please help

User IndyWill
by
5.6k points

2 Answers

3 votes

Answer:

Z = 0.198877274

Explanation:


((1)/(4))^(3z-1) = 16^z + 2*16^(z-2)\\4^(1-3z) = 4^(2z) + 4^{(1)/(2)}*4^(2z-4)\\4^(1-3z) = 4^(2z) + 4^{2z-4+(1)/(2)}\\4^(1-3z) = 4^(2z) + 4^{2z-(7)/(2)}\\4^(1-3z) = 4^(2z) *(1+ 4^{-(7)/(2)})\\4^(1-3z) = 4^(2z) *(1+ 2^(-7))\\4^(1-3z) = 4^(2z) *(1+ (1)/(128) )\\4^(1-3z) = 4^(2z) *((129)/(128) )\\Taking\;\; Logarithm\;\; with\;\; base\;\; 4\\Log_4(4^(1-3z)) = Log_4(4^(2z)) + Log_4((129)/(128))\\1-3z = 2z + 0.005613627712 \\5z = 0.994386372\\z = 0.198877274

Hence, the value of Z = 0.198877274

User John Conde
by
5.8k points
7 votes

Answer:

The value of z is
(3)/(8)

Explanation:

Given equation,


((1)/(4))^(3z-1)=16^(z+2).64^(z-2)


(1)/(4^(3z-1))=(4)^(2z+4).(4)^(3z-6)


4^(1-3z)=4^(2z+4+3z-6)
(a^m.a^n=a^(m+n)\text{ and }a^m=(1)/(a^(-m)))


4^(1-3z)=4^(5z-2)

By comparing the exponents,


1-3z=5z-2


-3z-5z=-2-1


-8z=-3


\implies z=(3)/(8)

User Rawoof Ahamed
by
5.2k points