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运用勾股定理解题应注意哪些问题呢?一、正确识别直角边和斜边例1 在△ABC中,∠A=90°,∠A、∠B、∠C的对边分别为a、b、c,且a=4,b=3。求c的长. 错解:由题意可知,△ABC为直角三角形. 由勾股定理可得c2=a2+b2=42+32=25.所以c=5. 剖析:在直角三角形中运用勾股定理时,首先要弄清楚哪个角是直角,从而确定哪条边是斜边,这样才能写出正确的勾股定理表达式.上述
What problems should be paid attention to when comprehending the comprehension questions? 1. Correctly identifying the right and left sides and oblique sides. Example 1 In △ABC, ∠A=90°, and the opposite sides of ∠A, ∠B, and ∠C are respectively a and b. c, and a=4, b=3. Find the length of c. Misunderstanding: From the meaning of the question, △ABC is a right-angled triangle. By the Pythagorean theorem, we can get c2=a2+b2=42+32=25. So c=5. Analysis: Apply the hook in the right triangle In the stock theorem, we must first figure out which corner is a right angle to determine which side is a hypotenuse, so as to write the correct Pythagorean theorem expression.