Current location - Training Enrollment Network - Mathematics courses - The most difficult geometric math problem in junior high school
The most difficult geometric math problem in junior high school
If we study the positive Xuan theorem and cosine theorem, then: area S=absinx/2. X is the angle corresponding to the C side. Cosx = (a 2+b 2-c 2)/(2ab), then sinx= under the radical sign (1-the square of cosx), and the final area is: let p=(a+b+c)/2.

The square of the area s =p(p-a)(p-b)(p-c) is obtained from the average inequality: S2 = p (p-a) (p-b) (p-c) "p * (p-a)+(p-b)+(p).