Chương I - Căn bậc hai. Căn bậc ba
Các câu hỏi tương tự
tìm x để các biểu thức sau có nghĩa :
a,sqrt{frac{4-x}{x+1}}
b,sqrt{frac{2x-3}{3x+1}}
c,sqrt{x^2-4}+sqrt{frac{x-2}{x+1}}
d,sqrt{frac{x^2-9}{x+1}}
e,sqrt{2x-1}+sqrt{x^3-4x^2-4x+16}
f,sqrt{2x-1}-sqrt{2x^3-11x^2+17x-6}
g,frac{1}{sqrt{x+3}+sqrt{x^2-1}}
Đọc tiếp
tìm x để các biểu thức sau có nghĩa :
a,\(\sqrt{\frac{4-x}{x+1}}\)
b,\(\sqrt{\frac{2x-3}{3x+1}}\)
c,\(\sqrt{x^2-4}+\sqrt{\frac{x-2}{x+1}}\)
d,\(\sqrt{\frac{x^2-9}{x+1}}\)
e,\(\sqrt{2x-1}+\sqrt{x^3-4x^2-4x+16}\)
f,\(\sqrt{2x-1}-\sqrt{2x^3-11x^2+17x-6}\)
g,\(\frac{1}{\sqrt{x+3}+\sqrt{x^2-1}}\)
Tìm điều kiện xác định
\(A=\sqrt{x^2-5x+6}\)
\(B=\dfrac{x}{\sqrt{7x^2-8}}\)
\(C=\sqrt{-9x^2+6x-1}-\dfrac{1}{\sqrt{x^2+x+2}}\)
\(D=\sqrt{3-x^2}-\sqrt{\dfrac{2021}{3x+2}}\)
\(E=\sqrt{\dfrac{3x^2}{2x+1}-1}\)
\(F=\sqrt{25x^2-10x+1}+\dfrac{1}{1-5x}\)
Tìm điều kiện xác định:
a) sqrt{-2x+3}
b) sqrt{frac{2}{x^2}}
c) sqrt{frac{4}{x+3}}
d) sqrt{frac{-5}{x^2+6}}
e) sqrt{3x+4}
f) sqrt{1+x^2}
g) sqrt{frac{3}{1-2x}}
h) sqrt{frac{-3}{3x+5}}
Đọc tiếp
Tìm điều kiện xác định:
a) \(\sqrt{-2x+3}\)
b) \(\sqrt{\frac{2}{x^2}}\)
c) \(\sqrt{\frac{4}{x+3}}\)
d) \(\sqrt{\frac{-5}{x^2+6}}\)
e) \(\sqrt{3x+4}\)
f) \(\sqrt{1+x^2}\)
g) \(\sqrt{\frac{3}{1-2x}}\)
h) \(\sqrt{\frac{-3}{3x+5}}\)
Tìm GTNN
A x² + 3x - 7
B x -5sqrt{x} -1
Cfrac{-4}{sqrt{x}+7}
D frac{sqrt{x}+1}{sqrt{x}+3}
E frac{x+7}{sqrt{x}+3}
F frac{x^2+3x+5}{x^2}
G frac{4x+1}{x^2+3}
H sqrt{x^2+2x+5}
Tìm GTLN
A -x² + 4x+3
B -x² + x + 1
C 5 - 3x +sqrt{x}
D frac{7}{sqrt{x}+3}
E frac{sqrt{x}+6}{sqrt{x}+1}
F frac{11}{x+3sqrt{x}+7}
Đọc tiếp
Tìm GTNN
A= x² + 3x - 7
B= x -5\(\sqrt{x}\) -1
C=\(\frac{-4}{\sqrt{x}+7}\)
D= \(\frac{\sqrt{x}+1}{\sqrt{x}+3}\)
E= \(\frac{x+7}{\sqrt{x}+3}\)
F= \(\frac{x^2+3x+5}{x^2}\)
G= \(\frac{4x+1}{x^2+3}\)
H= \(\sqrt{x^2+2x+5}\)
Tìm GTLN
A = -x² + 4x+3
B = -x² + x + 1
C = 5 - 3x +\(\sqrt{x}\)
D = \(\frac{7}{\sqrt{x}+3}\)
E = \(\frac{\sqrt{x}+6}{\sqrt{x}+1}\)
F = \(\frac{11}{x+3\sqrt{x}+7}\)
a)sqrt{x^2+2x+10}+x^2+2x+80
b)15x-2x^2-5sqrt{2x^2-15x+11}
c)sqrt{9x^2+45}+sqrt{16x^2+80}+3sqrt{frac{x^2+5}{16}}-frac{1}{4}sqrt{frac{25x^2+15}{9}}9
d)3x^2+21x+18+2sqrt{x^2+7x+7}2
e)sqrt{x^2+3x+2}-2sqrt{2x^2+6x+2}-sqrt{2}
f)sqrt{x-1}+sqrt{x+3}-sqrt{x^2+2x-3}-10
Đọc tiếp
a)\(\sqrt{x^2+2x+10}+x^2+2x+8=0\)
b)\(15x-2x^2-5=\sqrt{2x^2-15x+11}\)
c)\(\sqrt{9x^2+45}+\sqrt{16x^2+80}+3\sqrt{\frac{x^2+5}{16}}-\frac{1}{4}\sqrt{\frac{25x^2+15}{9}}=9\)
d)\(3x^2+21x+18+2\sqrt{x^2+7x+7}=2\)
e)\(\sqrt{x^2+3x+2}-2\sqrt{2x^2+6x+2}=-\sqrt{2}\)
f)\(\sqrt{x-1}+\sqrt{x+3}-\sqrt{x^2+2x-3}-1=0\)
Giải phương trình:
a) 2sqrt{x^2-4}-36sqrt{x-2}-sqrt{x+2}
b) frac{sqrt{x-2016}-1}{x-2016}+frac{sqrt{y-2017}-1}{y-2017}+frac{sqrt{z-2018}-1}{z-2018}frac{3}{4}
c) sqrt{3+sqrt{3+x}}x
d) sqrt{6x^2+1}sqrt{2x-3}+x^2
e) sqrt{x^2+3x+5}+sqrt{x^2-2x+5}5sqrt{x}
f) sqrt{x^2+3x}+2sqrt{x+2}2x+sqrt{x+frac{6}{x}+5}
Đọc tiếp
Giải phương trình:
a) \(2\sqrt{x^2-4}-3=6\sqrt{x-2}-\sqrt{x+2}\)
b) \(\frac{\sqrt{x-2016}-1}{x-2016}+\frac{\sqrt{y-2017}-1}{y-2017}+\frac{\sqrt{z-2018}-1}{z-2018}=\frac{3}{4}\)
c) \(\sqrt{3+\sqrt{3+x}}=x\)
d) \(\sqrt{6x^2+1}=\sqrt{2x-3}+x^2\)
e) \(\sqrt{x^2+3x+5}+\sqrt{x^2-2x+5}=5\sqrt{x}\)
f) \(\sqrt{x^2+3x}+2\sqrt{x+2}=2x+\sqrt{x+\frac{6}{x}+5}\)
tìm x để căn thức sau có nghĩa
a)sqrt{2x-1}
b)sqrt{4-x}
c)sqrt{frac{3x+1}{2}}
d)sqrt{x^2+1}
e)sqrt{x-2}+frac{1}{x^2-4}
f)sqrt{2x-1}+sqrt{3-x}
g)sqrt{frac{3}{x-1}}
h)sqrt{x^2-6x+9}
Đọc tiếp
tìm x để căn thức sau có nghĩa
a)\(\sqrt{2x-1}\)
b)\(\sqrt{4-x}\)
c)\(\sqrt{\frac{3x+1}{2}}\)
d)\(\sqrt{x^2+1}\)
e)\(\sqrt{x-2}+\frac{1}{x^2-4}\)
f)\(\sqrt{2x-1}+\sqrt{3-x}\)
g)\(\sqrt{\frac{3}{x-1}}\)
h)\(\sqrt{x^2-6x+9}\)
bài 1:
a) D sqrt{2-sqrt{3}}+sqrt{2+sqrt{3}}
b) E sqrt[3]{sqrt{5}-2}+sqrt[3]{sqrt{5}+2}
c) F sqrt[3]{182+sqrt{33125}}+sqrt[3]{182-sqrt{33125}}
bài 2:
a) C frac{1}{sqrt{2}+1}+frac{1}{sqrt{3}+sqrt{2}}+frac{1}{sqrt{4}+sqrt{3}}
b) D frac{3+2sqrt{3}}{sqrt{3}}+frac{2+sqrt{2}}{sqrt{2}+1}-frac{1}{2-sqrt{3}}
c) E frac{3-x^2}{x+sqrt{3}} với xne-sqrt{3}
d) F frac{1}{1+sqrt{2}}+frac{1}{sqrt{2}+sqrt{3}}+...+frac{1}{sqrt{2019}+sqrt{2020}}
e) G sqrt{2+sqrt{2+sqrt{2+sqrt{2+...}}}} (có vô hạn dấu căn)
Đọc tiếp
bài 1:
a) D = \(\sqrt{2-\sqrt{3}}+\sqrt{2+\sqrt{3}}\)
b) E = \(\sqrt[3]{\sqrt{5}-2}+\sqrt[3]{\sqrt{5}+2}\)
c) F =\(\sqrt[3]{182+\sqrt{33125}}+\sqrt[3]{182-\sqrt{33125}}\)
bài 2:
a) C = \(\frac{1}{\sqrt{2}+1}+\frac{1}{\sqrt{3}+\sqrt{2}}+\frac{1}{\sqrt{4}+\sqrt{3}}\)
b) D = \(\frac{3+2\sqrt{3}}{\sqrt{3}}+\frac{2+\sqrt{2}}{\sqrt{2}+1}-\frac{1}{2-\sqrt{3}}\)
c) E =\(\frac{3-x^2}{x+\sqrt{3}}\) với x\(\ne-\sqrt{3}\)
d) F = \(\frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{2}+\sqrt{3}}+...+\frac{1}{\sqrt{2019}+\sqrt{2020}}\)
e) G = \(\sqrt{2+\sqrt{2+\sqrt{2+\sqrt{2+...}}}}\) (có vô hạn dấu căn)
Tìm ĐKXĐ
a. \(3-\sqrt{1-16x^2}\)
b. \(\frac{1}{1-\sqrt{x^2-3}}\)
c.\(\sqrt{8x-x^2-15}\)
d. \(\frac{2}{\sqrt{x^2-x+1}}\)
e. \(A=\frac{1}{\sqrt{x-\sqrt{2x-1}}}\)
g. \(\frac{\sqrt{16-x^2}}{\sqrt{2x+1}}+\sqrt{x^2-8x+14}\)