> #bellenot\
# Project 6\
#3\
int(int(x^2+y,y=sqrt(x)..3),x=0..2);

                                            1/2
                                 16 - 16/7 2
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> #7\
int(int(x*y,y=x^2..sqrt(x)),x=0..1);

                                      1/12
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> #11\
int(int(exp(x/y),x=y..y^3),y=1..2);

                              1/2 exp(4) - 2 exp(1)
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> #15\
int(int(4*y^3,x=y^2..y+6),y=-2..3);

                                      500/3
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> #19\
int(int(x^2+y^2,y=x^2..sqrt(x)),x=0..1);

                                      6/35
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> #23\
int(int(sqrt(9-x^2),y=0..1-x/2),x=0..2);

                              1/2
                        11/6 5    + 9/2 arcsin(2/3) - 9/2
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> #27\
int(int(y,y=0..sqrt(1-x^2)),x=0..1);

                                       1/3
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> #31\
int(int(x^3*y^4+x*y^2,y=x^3-x..x^2+x),x=0..2);

                                   13984735616
                                   -----------
                                     14549535
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> #3\
int(int(r^2*cos(t)*sin(t)*r,r=2..5),t=0..Pi/2);

                                      609/8
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> #7\
int(int(r^3,r=t..2*t),t=0..2*Pi);

                                          5
                                     24 Pi
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>