Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) 50+3x(25-16)2+150
=50+3x92+1
=50+3x81+1
=50+243+1
=294
b)22x52-35/32
=(2x5)2-35-2
=102-33
=100-27
=73
c)80-[130-(12-4)2 ]
=80-[130-82 ]
=80-[130-64]
=80-66
=14
d)100:[2x(52-35-8)]
=100:[2x9]
=100:18
=100/18
e)24:{300:[375-(150+15x5)]}
=24:{300:[375-(150+75)]}
=24:{300:[375-225]}
=24:{300:50}
=24:6
=4
a)\(G=\frac{21^2.14.125}{35^5.6}=\frac{\left(3.7\right)^2.2.7.5^3}{\left(5.7\right)^5.2.3}=\frac{3^2.7^3.2.5^3}{5^5.7^5.2.3}=\frac{3}{5^2.7^2}=\frac{3}{35^2}=\frac{3}{1225}\)
b)\(H=\frac{45^3.20^4.18^2}{180^5}=\frac{\left(5.3^2\right)^3.\left(2^2.5\right)^4.\left(2.3^2\right)^2}{\left(5.3^2.2^2\right)^5}=\frac{5^3.3^6.2^8.5^4.2^2.3^4}{5^5.3^{10}.2^{10}}=\frac{5^7.2^{10}.3^{10}}{5^5.3^{10}.2^{10}}=5^2=25\)
\(=\frac{7.6^{11}.2^{19}.3^5-2^{19}.6^{15}}{3^{21}.2^{28}-3^{17}.2^{28}}=\frac{2^{19}.6^{11}.\left(7.3^5-6^4\right)}{3^{17}.2^{28}.\left(3^4-1\right)}=\frac{2^{30}.3^{11}.3^4.\left(7.3-2^4\right)}{3^{17}.2^{28}.\left(3^4-1\right)}=\frac{2^2.13}{3^2.80}=\frac{13}{9.20}=\frac{13}{180}\)
Tìm x
a.( x - 140 ) : 3 = 27
x - 140 = 27 . 3
x - 140 = 81
x = 221
b.14 - 4 ( x + 1 ) = 10
4 ( x + 1 ) = 14 - 10
4 ( x +1) = 4
x + 1 = 1
x = 0
c. 15 ( 7 - x ) = 15
7 - x = 1
x = 6
d.34 ( x - 3 ) = 0
\(\Rightarrow\) 34 = 0 hoặc x - 3 = 0
1. 34 = 0 ( vô lí )
2. x - 3 = 0 \(\Rightarrow\) x = 3
e. 24 + 6 (3 - x ) = 30
6( 3- x ) = 30 - 24
6( 3 - x ) = 6
3 - x = 1
x = 2
f. x3 + 24 = 51
x3 = 51 - 24
x3 = 27
\(\Rightarrow\)x = 3 ; x = -3
g. ( x- 5 )2 - 5 = 44
( x - 5) 2 = 49
\(\Rightarrow\)x - 5 = 7 hoặc x - 5 = -7
1. x - 5 = 7\(\Rightarrow\)x = 12
2. x - 5 = -7 \(\Rightarrow\)x = -2
h. ( x + 1 )3 - 23 = 4
( x + 1 )3 =27
\(\Rightarrow\) x + 1 = 3 hoặc x + 1 = -3
1. x + 1 = 3\(\Rightarrow\)x = 2
2. x + 1 = -3 \(\Rightarrow\)x = -4
Bài làm:
\(A=\frac{4^2}{15}.\frac{5^2}{24}.\frac{6^2}{35}.....\frac{20^2}{399}=\frac{4^2}{3.5}.\frac{5^2}{4.6}.\frac{6^2}{5.7}.....\frac{20^2}{19.21}=\frac{\left(4.5.6.....20\right)\left(4.5.6.....20\right)}{\left(3.4.5.....19\right)\left(5.6.7.....21\right)}=\frac{20.4}{3.21}=\frac{80}{63}\)
Học tốt!!!!