Hey I'm having some trouble with multiple integrals if anyone would care to explain (I think I'm just not using the correct region!)

I did the first part and got 0.8 as the answerEvaluate

first directly then changing the order of integration

just for the second I'm having trouble

I think the surface being integrated over the the triangle bounded by the lines y=x/2 x=0 and y=1 but I may be wrong which gives

but the value of that doesnt agree, can anyone explain how to do the limits correctly?

cheers

Simon