计算题,四题,要全,
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/17 01:19:48
![计算题,四题,要全,](/uploads/image/z/3150370-10-0.jpg?t=%E8%AE%A1%E7%AE%97%E9%A2%98%2C%E5%9B%9B%E9%A2%98%2C%E8%A6%81%E5%85%A8%2C)
xn@_
j5VJj{Bn-y|
xb v,6HAt@uUĊIDDY
oP73sN?ٿ8d۽Q]|~~q])ҤQ
计算题,四题,要全,
计算题,四题,要全,
计算题,四题,要全,
1题原式=√(m²n^4 +m^4 n²)
=√[m²n²(m²+n²)]
=√(m²n²)·√(m²+n²)
=mn√(m²+n²)
2题 ∵m²/(25n)≥0
∴n﹥0
原式=√[m²/(25n)]
=√[m²×(1/25)×n/n²]
=√m²×√(1/25)×√(1/n²)×√n
=m×1/5 ×1/n×√n
=(m√n)/(5n)
3题∵x﹥0 且 3y/(4x³)≥0
∴y≥0
原式=√[3y/(4x³)]
=√[3xy/(4x^4)]
=√[3xy×1/(2x²)²]
=√(3xy)×√[1/(2x²)]²
=[√(3xy)]/(2x²)
4题原式=√[(x²+y²)²(x²-y²)]
=√(x²+y²)²·√(x²-y²)
=(x²+y²)√(x²-y²)