Jawabanmu

2014-09-12T18:56:30+07:00
Masukin aja langsung ..
(fog) (x) = 4x2+8x-3 >> f(g(x)) , dimna g invers (x) = x/2-2= x-4/2
 
= 4(x-4/2)2+8(x-4/2)-3 |x4
=4x2-32x+64+16x-64-12
= 4x2-16x-12 << f(x) | :4
= x2-4x-3

tinggal cari f invers (x) :
f(x) = x2-4x-3                     | dimna f(x) = y ; x = x
y=(x-2)2-1         
y+1=(x-2)2
+- akar y+1 = x-2
x= 2 +- akar y+1 << inilah f invers (x)nya
f invers nya bisa gak kalo diganti jadi 2 + akar x+ 1 ?