Mathematics for IGCSE & O level - Functions (Section 1 - No. 1)
If f(x) = 2x-1, then f(g(x)) = 4x+3, find g(x).
2x+4
2x+2
4x+2
x+2
ব্যাখ্যা
Let g(x)=ax+b. Then f(g(x))=2(ax+b)-1 = 2ax+2b-1. We have 2ax+2b-1=4x+3. Then, 2a=4 and 2b-1=3, thus a=2 and b=2. So, g(x)=2x+2