F4 Math一問~~~~~

Method 1

g ( x-1 )=3^x-4 = 3^(x-1+1)-4 = [3^(x-1)]*3-4

put x-1=1,

g(1) = 5

Method 2

put x-1=1,
x=2

when x=2, g(1) = 3^2-4 = 5

Put x=2,

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

g( x - 1 ) = 3x-4
g( x - 1 ) = 3(x-1)-3
g (y) = 3y-3
When y = 1,
g(1) = 31-3
g(1) = 3-2
g(1) = 1/9