The score is too small. I'll make a point ...

First, A∩B contains two elements of 1/5, so there must be two elements of 1, 5 in B. Because B always has three elements, m and n are 1, 5 respectively, so M+N=6.

Second, to solve the equation, a set is {1,-1} and b is {0, 1}, so A∩B is {1} and a and b are {1,-65430.

Third, draw the number axis yourself in this question, and you can find the overlapping area of two areas, that is, P∩Q={X(0 is less than or equal to x is less than 1.

The fourth way, complement set, is that CuA={XX is less than the root number 2}

Fifth, AB should all be point sets. If you enter X in front and connect the two equations, you can get the answer {( 1, 2), (-4, 7)}.

The sixth method, by solving the set A, we can get 1

Finally, because the intersection is only 3, AB contains element 3, so the equation of 3 substituting into A and B must be satisfied, otherwise it is not their element. So substitute, get the solution, I do the oral calculation, P=8, Q=6, well, that's the only explanation.

Poor boy, I advise you to look through math books in the first half of senior one. Although it is a technical secondary school, you should know these basic things. Come on ~