1.计算1/(1+√2)+1/(√2+√3)+1/(√3+√4)+1/(√4+√5)+1/(√5+√6)2.若x=√5/2求[√(x+1)-√(x-1)/√(x+1)+√(x-1)]+[√(x+1)+√(x-1)/√(x+1)-√(x-1)]

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/08 14:06:27
1.计算1/(1+√2)+1/(√2+√3)+1/(√3+√4)+1/(√4+√5)+1/(√5+√6)2.若x=√5/2求[√(x+1)-√(x-1)/√(x+1)+√(x-1)]+[√(x+1)+√(x-1)/√(x+1)-√(x-1)]

1.计算1/(1+√2)+1/(√2+√3)+1/(√3+√4)+1/(√4+√5)+1/(√5+√6)2.若x=√5/2求[√(x+1)-√(x-1)/√(x+1)+√(x-1)]+[√(x+1)+√(x-1)/√(x+1)-√(x-1)]
1.计算1/(1+√2)+1/(√2+√3)+1/(√3+√4)+1/(√4+√5)+1/(√5+√6)
2.若x=√5/2求[√(x+1)-√(x-1)/√(x+1)+√(x-1)]+[√(x+1)+√(x-1)/√(x+1)-√(x-1)]

1.计算1/(1+√2)+1/(√2+√3)+1/(√3+√4)+1/(√4+√5)+1/(√5+√6)2.若x=√5/2求[√(x+1)-√(x-1)/√(x+1)+√(x-1)]+[√(x+1)+√(x-1)/√(x+1)-√(x-1)]
1.1/(1+√2)=(√2-1)/(1+√2)(1-√2)=√2-1
1/(√2+√3)=√3-√2
……
原式=√2-1+√3-√2+√4-√3+√5-√4+√6-√5=√6-1
2.原式={[√(x+1)-√(x-1)][√(x+1)-√(x-1)]/[√(x+1)+√(x-1)][√(x+1)-√(x-1)]} + {[√(x+1)+√(x-1)][√(x+1)+√(x-1)]/[√(x+1)-√(x-1)][√(x+1)+√(x-1)]}
=4x/2=2x
代入x=√5/2
原式=根号5

1,结果√6-1
2,√5