What is the answer to 4^{x-1}-18*2^{x-2}+8=0 ?

The answer to 4^{x-1}-18*2^{x-2}+8=0 is x=4,x=1

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4^{x-1}-18*2^{x-2}+8=0

4^{x - 1} - 18 \cdot 2^{x - 2} + 8 = 0

x = 4, x = 1

Solution steps

4^{x - 1} - 18 \cdot 2^{x - 2} + 8 = 0

Apply exponent rules

(2^{x})^{2} \cdot 2^{- 2} - 18 \cdot 2^{x} \cdot 2^{- 2} + 8 = 0

Rewrite the equation with

2^{x} = u

(u)^{2} \cdot 2^{- 2} - 18 u \cdot 2^{- 2} + 8 = 0

Solve

u^{2} \cdot 2^{- 2} - 18 u \cdot 2^{- 2} + 8 = 0 : u = 16, u = 2

u = 16, u = 2

Substitute back

u = 2^{x},

solve for

x

Solve

2^{x} = 16 : x = 4

Solve

2^{x} = 2 : x = 1

x = 4, x = 1

(2^{2 - x}) (4^{2 x + 3}) = 8

(\frac{1}{2})^{x} = 1

a, 2^{a} - 2^{b} = 2016

e^{x} = e^{x}

3 (3^{x})^{2} - 4 \cdot 3^{x} = - 1

What is the answer to 4^{x-1}-18*2^{x-2}+8=0 ?
The answer to 4^{x-1}-18*2^{x-2}+8=0 is x=4,x=1
Solve for x: 4^{x-1}-18*2^{x-2}+8=0
The solution is x=4,x=1