帮忙解一道数学题。高一的。

f(2)=3 2f(g(1))=f(1.5)=1.25

1.求f(2)和g(a)
f(2)=3, g(a)=1/2a+1.
2.求f〔g(1)〕和g〔f(x)〕
f〔g(1)〕=f(3/2)=5/4
g〔f(x)〕 =g(x²-1)=1/2(x²-1)+1

f(2) = 3 g(a) = 1/2a+1

f(g(1)) = 4/5 g(f(x)) = 1/2(x^2-1)+1

1，f(2)=3 ,g(a)=1/2*a+1
2, f{g(1)}=f(3/2)=5/4
g{f(x)}=1/2*x*x+1/2