论文部分内容阅读
近年来,“相交线与平行线”这一章内容不断涌现出一些新题型,这对培养我们的思维能力、解题能力和创新能力是大有好处的.下面我们就来看一看.一、共线型例1如图1,已知∠AOB与∠AOC互为补角,且∠AOC=∠BOD.试说明OA、OD在同一条直线上.解析:此题需求得∠AOD=180°,由平角的定义可说明OA、OD在同一条直线上.因为∠AOB与∠AOC互为补角,所以∠AOB+∠AOC=180°.又∠AOC=∠BOD,所以∠AOD=∠AOB+∠BOD=∠AOB+∠AOC=180°.由平角的定义知OA、OD在同一条直线上.
In recent years, the chapter “intersecting lines and parallel lines” is constantly emerging with new kinds of questions, which is of great benefit to us in cultivating our thinking ability, problem solving ability and innovative ability. See a. Collinear Example 1 As shown in Figure 1, it is known that ∠AOB and ∠AOC complement each other, and ∠AOC = ∠BOD. Test that OA, OD in the same straight line. AOD = 180 °, from the definition of flat angle can be described OA, OD in the same line. Because ∠ AOB and ∠ AOC complement each other angle, so ∠ AOB + ∠ AOC = 180 ° and ∠ AOC = ∠ BOD, so ∠ AOD = ∠AOB + ∠BOD = ∠AOB + ∠AOC = 180 ° from the definition of flat angle know OA, OD in the same straight line.