Plotting the diagram of the given function f(x)=maxx2,1+[x] we get,

Now when x∈[0,1)⇒f(x)=1
When x∈[1,2)⇒f(x)=2
And when x∈[2,2]⇒f(x)=x2
So, from above diagram area can be calculated as,
A=∫011.dx+∫122dx+∫22x2dx
⇒A=1+22−2+38−322
⇒A=35+342