【導讀】A.∠A=∠B=60°B.∠A=∠B=30°sinx=0.1523,x≈______;cosx=,x≈______;若AB=10,則BC=______,AC=_____,cosA=______;若BC=3x,則AB=______,AC=_____,tanA=______,tanB=______,sinB=_____.。若AC=5,BC=12,則AB=______,tanA=_______,∠A≈______;9.要加工形狀如圖的零件,請根據(jù)圖示尺寸計算斜角α的度數(shù).1.D2.8°45′37″68°12′37″59°59′57″。3.6,8,455x,4x,34,43,4536°52′12″,53°7′48″。5.31°47′56″6.26°33′54″7.2512128.75°57′50″