Tính bằng cách hợp lí :
\(\left(\dfrac{4}{9}-\dfrac{5}{11}\right):\dfrac{3}{10}+\left(\dfrac{3}{9}-\dfrac{9}{11}\right):\dfrac{3}{10}-\left(\dfrac{2}{9}-\dfrac{8}{11}\right).\left(\dfrac{-10}{3}\right)\)
Các bn giúp mik vs mai mik nộp bài r
\(\left(\dfrac{4}{9}-\dfrac{5}{11}\right):\dfrac{3}{10}+\left(\dfrac{3}{9}-\dfrac{9}{11}\right):\dfrac{3}{10}-\left(\dfrac{2}{9}-\dfrac{8}{11}\right)\cdot\left(-\dfrac{10}{3}\right)\\ =\left(\dfrac{4}{9}-\dfrac{5}{11}\right)\cdot\dfrac{10}{3}+\left(\dfrac{3}{9}-\dfrac{9}{11}\right)\cdot\dfrac{10}{3}-\left(\dfrac{2}{9}-\dfrac{8}{11}\right)\cdot\left(-1\right)\cdot\dfrac{10}{3}\\ =\left(\dfrac{4}{9}-\dfrac{5}{11}\right)\cdot\dfrac{10}{3}+\left(\dfrac{3}{9}-\dfrac{9}{11}\right)\cdot\dfrac{10}{3}+\left(\dfrac{2}{9}-\dfrac{8}{11}\right)\cdot\dfrac{10}{3}=\dfrac{10}{3}\cdot\left(\dfrac{4}{9}-\dfrac{5}{11}+\dfrac{3}{9}-\dfrac{9}{11}+\dfrac{2}{9}-\dfrac{8}{11}\right)\\ =\dfrac{10}{3}\cdot\left(-1\right)\\ =-\dfrac{10}{3}\)
Tìm số tự nhiên n
\(2n+2^{n+1}=24\)
\(\dfrac{125}{\left(-5\right)^n}=-25\)
\(\dfrac{n-2}{4}=\dfrac{1}{2}\)
Tìm x biết
a,(x-3)2=1
b,(x-\(\dfrac{1}{7}\))2=0
c,(2x+3)3=-27
d,(x+\(\dfrac{1}{2}\))2=\(\dfrac{1}{4}\)
e,-(5+35x)2=36
Biết rằng 12+ 22 +-.+102 = 385
Tính nhanh ( 122 + 142 + 162 + 182 + 202)- ( 12 + 32 + 52 + 72 + 92)
Tính
\(A=\left(1-\dfrac{1}{2^2}\right)\left(1-\dfrac{1}{3^2}\right)\left(1-\dfrac{1}{4^2}\right)...\left(1-\dfrac{1}{n^2}\right)\left(n\in N,n\ge2\right)\)
\(\dfrac{16^3.3^{10}+120.6^9}{4^6.3^{12}+6^{11}}\)
\(\left(-5\right)^{2x+1}=\dfrac{-1}{125}\)
Giải giúp với nha anh em
1. Tìm x,y biết:
\(\left(x-2\right)^{20}+\left(y+1\right)^{30}\le0\)
Giúp mk vs
Chứng minh
( 2,57+3,56+4,55) chia hết cho 69
1: Tính : \(\dfrac{\left(\dfrac{2}{5}\right)^7.5^7+\left(\dfrac{9}{4}\right)^3:\left(\dfrac{3}{16}\right)^3}{2^7.5^2+512}\) 2 . Tìm x biết :\(\left(5.x+1\right)^2=\dfrac{36}{49}\)
Tính
a) ( \(\dfrac{2}{5}\)+ \(\dfrac{3}{4}\))2
b) ( \(\dfrac{5}{4}\)- \(\dfrac{1}{6}\)) 2
Loga.vn - Cộng Đồng Luyện Thi Trực Tuyến