计算各式:①4√5+√45-√8+√32=___; ②√4/3 ÷ √8/3 × √8/5=____ ③﹙2√3+√5﹚﹙2√3-√5﹚=____
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![计算各式:①4√5+√45-√8+√32=___; ②√4/3 ÷ √8/3 × √8/5=____ ③﹙2√3+√5﹚﹙2√3-√5﹚=____](/uploads/image/z/186148-28-8.jpg?t=%E8%AE%A1%E7%AE%97%E5%90%84%E5%BC%8F%3A%E2%91%A04%E2%88%9A5%2B%E2%88%9A45-%E2%88%9A8%2B%E2%88%9A32%3D___%3B+%E2%91%A1%E2%88%9A4%2F3+%C3%B7+%E2%88%9A8%2F3+%C3%97+%E2%88%9A8%2F5%3D____+%E2%91%A2%EF%B9%992%E2%88%9A3%2B%E2%88%9A5%EF%B9%9A%EF%B9%992%E2%88%9A3-%E2%88%9A5%EF%B9%9A%3D____)
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计算各式:①4√5+√45-√8+√32=___; ②√4/3 ÷ √8/3 × √8/5=____ ③﹙2√3+√5﹚﹙2√3-√5﹚=____
计算各式:①4√5+√45-√8+√32=___; ②√4/3 ÷ √8/3 × √8/5=____ ③﹙2√3+√5﹚﹙2√3-√5﹚=____
计算各式:①4√5+√45-√8+√32=___; ②√4/3 ÷ √8/3 × √8/5=____ ③﹙2√3+√5﹚﹙2√3-√5﹚=____
①4√5+√45-√8+√32
=4√5+3√5-2√2+4√2
=7√5+2√2
②√4/3 ÷ √8/3 × √8/5
=2/3÷ 2√2/3× 2√2/5
=2/3×3/2√2× 2√2/5
=1/√2× 2√2/5
=2/5
③﹙2√3+√5﹚﹙2√3-√5﹚
=﹙2√3)^2-(√5﹚^2
;=12-25
=-13
解:
①4√5+√45-√8+√32
=4√5+3√5-2√2+4√2
=7√5+2√2
②√4/3 ÷ √8/3 × √8/5
=√4÷√8 × √8/5
=√4/√8 × √8/5
=√4/5
=2/5
③﹙2√3+√5﹚﹙2√3-√5﹚
=﹙2√3)²-(√5﹚²
=12-25
=-13
我是最先作答的啊,伤心