Toán rút gọn A= 7. √16a^6 -5a ³ vs a<0 B=5. √49a^4+3a ² vs a>0 17/07/2021 By Charlie rút gọn A= 7. √16a^6 -5a ³ vs a<0 B=5. √49a^4+3a ² vs a>0
`A= 7. \sqrt{16a^6} -5a^3` `A=7. \sqrt{(4a^3)^2} -5a^3` `A=7. |4a^3| -5a^3` `A=7.(-4a^3)-5a^3` `(a<0)` `A=-28a^3-5a^3` `A=-33a^3` Đáp án: `A=-33a^3` `B=5. \sqrt{49a^4}+3a^2` `B=5. \sqrt{(7a^2)^2}+3a^2` `B=5. |(7a^2)|+3a^2` `B=5.7a^2+3a^2` `(a>0)` `B=35a^2+3a^2` `B=38a^2` Đáp án: `B=38a^2` Trả lời
`A= 7. \sqrt{16a^6} -5a^3`
`A=7. \sqrt{(4a^3)^2} -5a^3`
`A=7. |4a^3| -5a^3`
`A=7.(-4a^3)-5a^3` `(a<0)`
`A=-28a^3-5a^3`
`A=-33a^3`
Đáp án: `A=-33a^3`
`B=5. \sqrt{49a^4}+3a^2`
`B=5. \sqrt{(7a^2)^2}+3a^2`
`B=5. |(7a^2)|+3a^2`
`B=5.7a^2+3a^2` `(a>0)`
`B=35a^2+3a^2`
`B=38a^2`
Đáp án: `B=38a^2`