Question

【題目】如圖，Rt△AOB繞著一點(diǎn)旋轉(zhuǎn)到△A′OB′的位置，可以看到點(diǎn)A旋轉(zhuǎn)到點(diǎn)A′，OA旋轉(zhuǎn)到OA′，∠AOB旋轉(zhuǎn)到∠A′OB′，這些都是互相對(duì)應(yīng)的點(diǎn)、線段和角．已知∠AOB＝30°，∠AOB′＝10°，那么點(diǎn)B的對(duì)應(yīng)點(diǎn)是點(diǎn)______；線段OB的對(duì)應(yīng)線段是線段_____；∠A的對(duì)應(yīng)角是______；旋轉(zhuǎn)中心是點(diǎn)_______；旋轉(zhuǎn)的角度是______度．

Answer 1

【答案】 B′ OB′ ∠A′ O 40

【解析】試題解析：∵A與A′、OA與OA′、與分別是相互對(duì)應(yīng)的點(diǎn)、線、角，

∴點(diǎn)B的對(duì)應(yīng)點(diǎn)為點(diǎn)B′，點(diǎn)O為旋轉(zhuǎn)中心，

∴線段OB的對(duì)應(yīng)線段為OB′，∠A的對(duì)應(yīng)角是

∵對(duì)應(yīng)點(diǎn)與旋轉(zhuǎn)中心連線的夾角為旋轉(zhuǎn)角，

∴均為旋轉(zhuǎn)角.

故答案為:B′、OB′、∠A′、O、.