(x2-4x-12)(x2-2x-15)=180
<=> x4-6x3-19x2+84x=0
<=> x(x3-6x2-19x+84)=0
<=>x(x+4)(x-7)(x-3)=0
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-4\\x=7\\x=3\end{matrix}\right.\)
Vậy.............
Chương 3: PHƯƠNG TRÌNH, HỆ PHƯƠNG TRÌNH
Các câu hỏi tương tự
\(\frac{x^2+x+1}{x^2+2x+1}+\frac{x^2+3x+1}{x^2+4x+1}=\frac{19}{12}\)
\(\dfrac{x+1}{x^2+2x}+\dfrac{x+6}{x^2+12x+35}=\dfrac{x+2}{x^2+4x+3}-\dfrac{x+15}{x^2+10x+24}\)
\(x^2-4x-6=2\sqrt{2x^2-8x+12}\)
1 tháng 10 2019 lúc 22:22
giai pt:
a) \(\sqrt{x^2-4x-12}=9-2x\)
b) \(\left(x+1\right)\sqrt[3]{15x^2-x-1}=x^2-1\)
c) \(\left(2x-2\right)\sqrt{2x-1}=6\left(x-1\right)\)
d) \(\frac{\sqrt{-x^2+4x-3}-1}{x-3}=2\)
e) \(\frac{5+\sqrt{x+1}}{x-2}=7\)
22 tháng 10 2019 lúc 16:29
Giải pt
a) \(x^2-2x+3\sqrt{x^2-2x-3}=7\)
b) \(\left(x-2\right)^2+2=\sqrt{x^2-4x+12}\)
c) \(x^2+\sqrt{x^2+11}=31\)
d) \(\sqrt{2x^2+4x+1}=1-x\left(x+2\right)\)
e) \(\left(x+1\right)\left(x+4\right)=5\sqrt{x^2+5x+28}\)
Giải phương trình:
a) sqrt{x+2}sqrt{2x+1}+xsqrt{x+2}
b) 2+sqrt{3-8x}6x+sqrt{4x-1}
c) sqrt{10x+1}+sqrt{3x-5}sqrt{9x+4}+sqrt{2x-1}
d) 1+sqrt{x^2+4x}sqrt{x^2-3x+3}+sqrt{2x^2+x+2}
e) sqrt{x^2+15}3x-2+sqrt{x^2+8}
f) left(sqrt{x+5}-sqrt{x+2}right)left(1+sqrt{x^2+7x+10}right)3
g) sqrt{3x^2-7x+3}-sqrt{x^2-2}sqrt{3x^2-5x-1}-sqrt{x^2-3x+4}
h) sqrt{2x^2+x-1}+sqrt{3x^2+x-1}sqrt{x^2+4x-3}+sqrt{2x^2+4x-3}
Đọc tiếp
Giải phương trình:
a) \(\sqrt{x+2}=\sqrt{2x+1}+x\sqrt{x+2}\)
b) \(2+\sqrt{3-8x}=6x+\sqrt{4x-1}\)
c) \(\sqrt{10x+1}+\sqrt{3x-5}=\sqrt{9x+4}+\sqrt{2x-1}\)
d) \(1+\sqrt{x^2+4x}=\sqrt{x^2-3x+3}+\sqrt{2x^2+x+2}\)
e) \(\sqrt{x^2+15}=3x-2+\sqrt{x^2+8}\)
f) \(\left(\sqrt{x+5}-\sqrt{x+2}\right)\left(1+\sqrt{x^2+7x+10}\right)=3\)
g) \(\sqrt{3x^2-7x+3}-\sqrt{x^2-2}=\sqrt{3x^2-5x-1}-\sqrt{x^2-3x+4}\)
h) \(\sqrt{2x^2+x-1}+\sqrt{3x^2+x-1}=\sqrt{x^2+4x-3}+\sqrt{2x^2+4x-3}\)
Giải phương trình:1. x^4-6x^2-12x-802. dfrac{x}{2x^2+4x+1}+dfrac{x}{2x^2-4x+1}dfrac{3}{5}3. x^4-x^3-8x^2+9x-9+left(x^2-x+1right)sqrt{x+9}04. 2x^2.sqrt{-4x^4+4x^2+3}4x^4+15. x^2+4x+3sqrt{dfrac{x}{8}+dfrac{1}{2}}6. left{{}begin{matrix}4x^3+xy^23x-y4xy+y^22end{matrix}right.7. left{{}begin{matrix}sqrt{x^2-3y}left(2x+y+1right)+2x+y-505x^2+y^2+4xy-3y-50end{matrix}right.8. left{{}begin{matrix}sqrt{2x^2+2}+left(x^2+1right)^2+2y-100left(x^2+1right)^2+x^2yleft(y-4right)0end{matrix}right.
Đọc tiếp
Giải phương trình:
1. \(x^4-6x^2-12x-8=0\)
2. \(\dfrac{x}{2x^2+4x+1}+\dfrac{x}{2x^2-4x+1}=\dfrac{3}{5}\)
3. \(x^4-x^3-8x^2+9x-9+\left(x^2-x+1\right)\sqrt{x+9}=0\)
4. \(2x^2.\sqrt{-4x^4+4x^2+3}=4x^4+1\)
5. \(x^2+4x+3=\sqrt{\dfrac{x}{8}+\dfrac{1}{2}}\)
6. \(\left\{{}\begin{matrix}4x^3+xy^2=3x-y\\4xy+y^2=2\end{matrix}\right.\)
7. \(\left\{{}\begin{matrix}\sqrt{x^2-3y}\left(2x+y+1\right)+2x+y-5=0\\5x^2+y^2+4xy-3y-5=0\end{matrix}\right.\)
8. \(\left\{{}\begin{matrix}\sqrt{2x^2+2}+\left(x^2+1\right)^2+2y-10=0\\\left(x^2+1\right)^2+x^2y\left(y-4\right)=0\end{matrix}\right.\)
22 tháng 10 2019 lúc 17:12
Giải pt
a) 2x^2+sqrt{x^2-5x-6}10x+15
b) 5sqrt{3x^2-4x-2}-6x^2+8x+70
c) x^2+sqrt{2x^2+4x+3}6-2x
d) 2sqrt{frac{3x-1}{x}}frac{x}{3x-1}+1
e) sqrt{frac{24x-4}{x}}frac{x}{6x-1}+1
f) sqrt{frac{2x-1}{x}}+1+sqrt{frac{x}{2x-1}}frac{3x}{2x-1}
Đọc tiếp
Giải pt
a) \(2x^2+\sqrt{x^2-5x-6}=10x+15\)
b) \(5\sqrt{3x^2-4x-2}-6x^2+8x+7=0\)
c) \(x^2+\sqrt{2x^2+4x+3}=6-2x\)
d) \(2\sqrt{\frac{3x-1}{x}}=\frac{x}{3x-1}+1\)
e) \(\sqrt{\frac{24x-4}{x}}=\frac{x}{6x-1}+1\)
f) \(\sqrt{\frac{2x-1}{x}}+1+\sqrt{\frac{x}{2x-1}}=\frac{3x}{2x-1}\)
1 tháng 10 2019 lúc 22:41
giải pt
a) \(x\sqrt{x^2-4x+3}=x^2+x\)
b) \(x^2+x-12-\left(x-3\right)\sqrt{10-x^2}=0\)
c) \(\sqrt{6+x-x^2}=\frac{\left(2x+5\right)\sqrt{6+x-x^2}}{x+4}\)
d) \(\sqrt{\frac{12+x-x^2}{2x+9}}-\frac{\sqrt{12+x-x^2}}{x+3}=0\)
e) \(\sqrt{x^3}+\sqrt{x^3+x^2+2x}=3\sqrt{x}\)