Các câu hỏi tương tự
So sánh:a)Asqrt[]{21}+sqrt{42}+sqrt{63}Bsqrt{1}+sqrt{2}+sqrt{3}+sqrt{20}+sqrt{40}+sqrt{60}b)Aleft(1-frac{1}{sqrt{4}}right)left(1-frac{1}{sqrt{16}}right)left(1-frac{1}{sqrt{100}}right)Bsqrt{0,1}c) Afrac{1}{sqrt{1}}+frac{1}{sqrt{2}}+...+frac{1}{sqrt{100}}B10
Đọc tiếp
So sánh:
a)\(A=\sqrt[]{21}+\sqrt{42}+\sqrt{63}\)
\(B=\sqrt{1}+\sqrt{2}+\sqrt{3}+\sqrt{20}+\sqrt{40}+\sqrt{60}\)
b)\(A=\left(1-\frac{1}{\sqrt{4}}\right)\left(1-\frac{1}{\sqrt{16}}\right)\left(1-\frac{1}{\sqrt{100}}\right)\)
\(B=\sqrt{0,1}\)
c) \(A=\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+...+\frac{1}{\sqrt{100}}\)
\(B=10\)
So sánh A và B :
a)
\(A=\sqrt{20+1}+\sqrt{40+2}+\sqrt{60+3}\)
\(B=\sqrt{1}+\sqrt{2}+\sqrt{3}+\sqrt{20}+\sqrt{40}+\sqrt{60}\)
b)
\(A=\frac{1}{\sqrt{121}}+\frac{1}{\sqrt{12321}}+\frac{1}{\sqrt{1234321}}+...+\frac{1}{\sqrt{12345678987654321}}\)
\(B=0,111111111\)
Tính:
a) A=\(\sqrt{18}+\sqrt{50}-\frac{1}{2}\sqrt{98}\)
b) B=\(\left(2\sqrt{3}+7\right)\left(2\sqrt{3}-7\right)\)
c) C=\(\sqrt{7-2\sqrt{10}+\sqrt{2}}\)
Chứng minh rằng a,\(\sqrt{2}+\sqrt{6}+\sqrt{12}+\sqrt{20}+\sqrt{30}+\sqrt{42}< 24\)
b,\(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}>10\)
Tính :
a, \((\sqrt{2}-\sqrt{3}).\left(\sqrt{2}+\sqrt{3}\right)\)
b, \(-(\sqrt{2})^4+\left(\sqrt{3}\right)^6\)
c , \(A=\frac{1}{1-\frac{1}{1-2^{-4}}}+\frac{1}{1+\frac{1}{1+2^{-1}}}\)
d, B = 9 + 99 + 999 + .... + 9999...9
( 50 chữ số 9 )
Tính
a) \(2\sqrt{\frac{25}{16}}-3\sqrt{\frac{49}{36}}+4\sqrt{\frac{81}{64}}\)
b) \(\left(3\sqrt{2}\right)^2-\left(4\sqrt{\frac{1}{2}}\right)^2+\frac{1}{16}.\left(\sqrt{\frac{3}{4}}\right)^2\)
c) \(\frac{2}{3}\sqrt{\frac{81}{16}}-\frac{3}{4}\sqrt{\frac{64}{9}}+\frac{7}{5}.\sqrt{\frac{25}{196}}\)
a,
\(x=3\sqrt{2
}\)
\(y=2\sqrt{3}\)
b,
\(x=\sqrt{3}+\sqrt{6}\)
\(y=\sqrt{2}+\sqrt{7}\)
c,
\(x=-\frac{1}{2}\sqrt{\frac{1}{3}}\)
\(y=-\frac{1}{3}\sqrt{-\frac{1}{2}}\)
Chứng minh rằng:
a)\(\sqrt{1}+\sqrt{2}+...+\sqrt{8}< 24\)
b)\(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+...+\frac{1}{\sqrt{100}}>10\)
c)\(\sqrt{6}+\sqrt{12}+\sqrt{20}+\sqrt{30}+\sqrt{42}+\sqrt{56}< 30\)
Giúp mik với
Ko dùng máy tinnhs,hãy so sánh các số sau
a.\(\sqrt{15}+2\)và \(7\)
b.\(\sqrt{26}-5\)và\(3-\sqrt{10}\)
c.\(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}\)và 10