如题所述
8-(6/7除以3/14+11/21)计算
8-(6/7除以3/14+11/21)
=8-(4+11/21)
=8-4-11/21
=4-11/21
=3又10/21
1 计算(1)6√14除以8√18 (2)-√7÷3√14/15*3/2√5/2
1 计算(1)6√14除以8√18
=6√14/24√2
=√7/4
(2)-√7÷3√14/15*3/2√5/2
=√2/5*3√10/4
=3√5/10 题目有点不太清楚
3)2√xy的三次方÷(-1/2√x的三次方y的平方)
=-4√y/x
(4)√ab的三次方÷(-3√b/2a)乘√2a
=-ab√2×√2a
=-2ab√a
(5)√27×(-5√3)
=3√3×(-5√3)
=-45
(6)8√x的三次方y÷√2x
=4x√2
(7) √m/n乘以(√n/m÷√1/n)
=√(m/n)×√(n/m)×√n
=√n
化简(1)√18乘以50
=150√2
(2) √(26/25)的平方-(2/5)的平方
=26/25-4/25
=22/25
化简的√(7/2)的平方
=7/2
总的少一些括号,所以不能保证所有的都正确
6/7除以【(11/12-3/4)乘以9/14】 简便计算
先把小括号里面的算出来,在把大括号去掉,即为6/7乘以6乘以14/9,再约分
6/7除以11/24一3/8x4/11
=6/724/11-1/812/11
=12/11(12/11-1/8)
=12/11
(37/14+11/21)除以19/4
(37/14+11/21)除以19/4
=(111/42+22/42)*4/19
=133/42*4/19
=2/3
1/56除以(3/14除以6/13)
1/56除以(3/14除以6/13)
=(1/56)/(3/14*13/6)
=(1/56)/13/28)
=1/56*28/13
=2/13
简便方法计算 ①2/7×42×6/5 ②3/4x[5/8-(3/7-3/8)] ③96x95/97
简便方法计算 ①2/7×42×6/5
=2*6*6/5
=72/5
= 14.4
②3/4x[5/8-(3/7-3/8)]
=3/4*5/8-(3/4*3/7-3/4*3/8)
=15/32-(9/28-9/32)
=15/32-9/28+9/32
=(15/32+9/32)-9/28
=24/32-9/28
=3/4-9/28
=21/28-9/28
=12/28
=3/7
③96x95/97
=(97-1)*95/97
=97*95/97-1*95/97
=95-95/97
=94又2/97
(1) 5/8X3+5/8 (2) 45除以9/14 (3)2/9X0.375除以6/7 怎样计算
(1) 5/8X3+5/8
=5/8X(3+1)
=5/8X4
=5/2
(2) 45除以9/14
=45X14/9
=5X14
=70
(3)2/9X0.375除以6/7
=2/9X3/8X6/7
=1/12X6/7
=1/14
计算13又8/13除以6+7又2/13除以(-6)+(-36又6/13)除以6
=(13又8/13-7又2/13-36又6/13)x1/6
=(13-7-36+8/13-2/13-6/13)x1/6
=-5
九又6/7×3/10加3/10×9/21简便计算
九又6/7×3/10加3/10×9/21
=3/10×(九又6/7+9/21)
=3/10×(69/7+9/21)
=3/10×(207/21+9/21)
=3/10×216/21
=108/35