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Help urgently for a maths exponential equation
just need a and b!!

Help urgently for a maths exponential equation just need a and b!!-example-1
User JCorcuera
by
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1 Answer

5 votes

2a)


\rightarrow \sf 2^(x+1) = 2^x + 4


\rightarrow \sf 2^(x+1) -2^x = 4


\rightarrow \sf 2^1 * 2^x -2^x = 2^2


\rightarrow \sf 2^x\left(2^1-1\right) = 2^2


\rightarrow \sf 2^x\left(1) = 2^2


\rightarrow \sf 2^x = 2^2


\rightarrow \sf x= 2

2b)


\rightarrow \sf 2^x + 2^(x - 2) = 5


\rightarrow \sf 2^x + 2^(x) / 2^2 = 5


\rightarrow \sf 2^x + (2^(x))/(2^2) = 5


\rightarrow \sf 2^x(1 + (1)/(4) ) = 5


\rightarrow \sf 2^x(1.25 ) = 5


\rightarrow \sf 2^x = 5 / 1.25


\rightarrow \sf 2^x =4


\rightarrow \sf 2^x =2^2


\rightarrow \sf x=2

User Gilco
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