The outlook of pattern is unstable. The patterns are different becaues of the different angles. In thepaper of pattern regcognition, how to recognize correctly from different angles and enhence the validity of pattern recognition is very important. This paper decribes how to use the math to decrease inaccuracy and enhence the validity. First, we use the computer to find out the maximun inaccuracy of the 3 points of pattern from the different angles. And then using the triangle geometry to minimize the inaccuracy. Under different condition, using the computer to found out three of the max inaccurate points of the patterns from the different angles, and conneceing the three points and form two triangles. Finally, we try to minimize the sum of the distance of relative apex by mathematical operation