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Mathematical tree list method
First, draw a tree diagram according to the meaning of the question, and then get all the equal possible results from the tree diagram and the equation x2+px+q=0 about X with real roots, and then use the probability formula to get the answer.

Answer:

Solution: Draw a tree diagram.

So: ∵x2+px+q=0 has real roots,

∴△=b2-4ac=p2-4q≥0,

∫ * * There are six equal possible results, and there are (1,-1), (2,-1), (2, 1) * * three cases about X that satisfy the equation x2+px = 0.

∴ The probability that the equation x2+px+q=0 about X has a real root is: 3/6 = 1 /2.

This topic examines the knowledge of finding probability and discriminant of quadratic equation in one variable by list method or tree diagram method. Note that the tree diagram method and the list method can list all possible results without repetition or omission, and the list method is suitable for two-step events; Tree diagram method is suitable for events completed in two or more steps; Pay attention to whether this problem is put back into the experiment; Attention probability = the ratio of the number of cases requested to the total number of cases.