a) Đúng
b) \(\sqrt{1^3+2^3+3^3+4^3}=1+2+3+4\)
\(\sqrt{1^3+2^3+3^3+4^3+5^3=1+2+3+4+5}\)
a) Đúng
b) \(\sqrt{1^3+2^3+3^3+4^3}=1+2+3+4\)
\(\sqrt{1^3+2^3+3^3+4^3+5^3=1+2+3+4+5}\)
So sánh
a) 3*\(\sqrt{2}\) và 7, (21)
b) \(\frac{1}{\sqrt{1}+\sqrt{2}}\) + \(\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+.....+\frac{1}{\sqrt{99}+\sqrt{100}}\) và 9
Bài 1:
a) \(\left(2-\sqrt{3}\right).\left(2+\sqrt{3}\right)+\sqrt{2}.\dfrac{\sqrt{2^5}}{1-\sqrt{9}}\)
b)\(\left(\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+...+\dfrac{1}{49.50}\right).\dfrac{49}{50}\)
Cảm ơn trước nha
Bai 1:Tinh: \(\sqrt{1}\) - \(\sqrt{4}\) + \(\sqrt{9}\) - \(\sqrt{16}\) + \(\sqrt{25}\)- \(\sqrt{36}\)+........- \(\sqrt{400}\)
Bai 2: Thuc hien phep tinh (bang cach hop li neu co the)
a, 15/34+7/21+19/24-1\(\dfrac{15}{17}\)+2/3 c, 1/2+3/2*5/6
b,\(\sqrt{25}\)+3^2-\(\sqrt{9}\)
Bai 3 : mot lop hoc co 35 hs sau khi khao sat so hs duoc xep thanh ba loai gioi,kha ,
trung binh.So hs gioi va kha ti le voi 2 va 3 ; so hs kha va trung binh la luot ti le voi 4 va 5 .Tinh
so hs moi loai?
Bai 4 : thuc hien phep tinh sau do lam tron den chu so thap hpan thu nhat
a, -5,18-0,479 c, ( | -2,45| + 3,1)*1/2 - 3/4
b, (3-1/2)^2 + (1-5/2)^2
a) \(\left|2x-1\right|+\left|x+8\right|=4x\)
b) \(\left(\sqrt{x+1}\right)\left(\sqrt{x-3}\right)=0\)
c) \(3^x+3^{x+2}=2430\)
a,\(\left(\frac{2^2}{5}\right)\)+\(5\frac{1}{2}\).(4,5-2,5)+\(\frac{2^3}{-4}\)
b,\(\left(-2^3\right)\)+\(\frac{1}{2}\):\(\frac{1}{8}\)-\(\sqrt{25}\)+|-64|
c,\(\frac{\sqrt{3^2+\sqrt{39}^2}}{\sqrt{91^2}-\sqrt{\left(-7^2\right)}}\)
d,\(\left(-2^2\right)+\sqrt{36}-\sqrt{9}+\sqrt{25}20.20\))
e,\(\sqrt{25}-3\sqrt{\frac{4}{9}}\)
h,\(\left(-3^2\right)\).\(\frac{1}{3}\)-\(\sqrt{49}\)+\(\left(5^3\right)\):\(\sqrt{25}\)
Tính:
\(\left(\dfrac{9}{25}-2.18\right):\left(3\dfrac{4}{5}+0,2\right)\)
\(\dfrac{3}{8}.19\dfrac{1}{3}\dfrac{3}{8}.33\dfrac{1}{3}\)
\(15.\left(-\dfrac{2}{3}\right)^2-\dfrac{7}{3}\)
\(\dfrac{1}{2}\sqrt{64}-\sqrt{\dfrac{4}{25}}+\left(-1\right)^{2007}\)
\(\left(-\dfrac{5}{2}\right)^2:\left(-15\right)-\left(0,45+\dfrac{3}{4}\right).\left(-1\dfrac{5}{9}\right)\)
\(\left(\dfrac{-1}{3}\right)-\left(\dfrac{-3}{5}\right)^0+\left(1-\dfrac{1}{2}\right)^2:2\)
\(\left(\dfrac{1}{2}\right)^{15}.\left(\dfrac{1}{4}\right)^{20}\)
\(\dfrac{5^4.20}{25^5.4^5}\)
Bài 1: Tìm các số nguyên n sau cho các biểu thức sau là số nguyên:P= \(\dfrac{5n+7}{n-2}\) ; Q= \(\dfrac{3\sqrt{n}+5}{\sqrt{n}-1}\)
Bài 1:Tính bằng cách hợp lý (nếu có thể)
a,\(16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)+28\dfrac{2}{7}:\dfrac{3}{5}\)
b,\(\dfrac{3}{5}:\left(\dfrac{-1}{15}-\dfrac{1}{6}\right)+\dfrac{3}{5}:\left(\dfrac{-1}{3}-1\dfrac{1}{15}\right)\)
c,\(\left(-6,5\right).5,7+5,7.\left(-3.5\right)\)
d,\(10.\sqrt{0,01.}\sqrt{ }\dfrac{16}{9}+3\sqrt{49}-\dfrac{1}{6}\sqrt{4}\)
1, So sánh A và B, biết
a, A= \(\sqrt{20+1}\) + \(\sqrt{40+2}\) + \(\sqrt{60+3}\)
B= \(\sqrt{1}\) + \(\sqrt{2}\) + \(\sqrt{3}\) + \(\sqrt{20}\) + \(\sqrt{40}\) + \(\sqrt{60}\)