1/giai pt a) \(\left(2x+7\right)\sqrt{2x+7}=x^2+9x+7\)
b)\(\left(\sqrt{x+5}-\sqrt{x+2}\right)\left(1+\sqrt{x^2+7x+10}\right)=3\)
c)\(\sqrt{\left(9-4x\right)\left(x^2-6x+9\right)}=\left|-2x+5\right|\sqrt{9-4x}\)
2/giai va bien luan pt \(\left|x+3\right|+p\left|x-2\right|=5\)(p la tham so cp gia tri thuc)
3/cho 2pt \(x^2+bx+c=0\)(1) va \(x^2-b^2x+bc=0\)(2)
biet pt (1) co 2 nghiem \(x_1,x_2\) va pt(2) co 2 nghiem \(x_3,x_4\) thoa man \(x_3-x_1=x_4-x_2=1\) .tim \(b\) va \(c\)
Cho 2 phương trình \(x^2+bx+c=0\left(1\right)\)và \(x^2-b^2x+bc=0\left(2\right)\)( trong đó x là ẩn số , b và c là các tham số ) . Biết pt ( 1 ) có 2 nghiệm \(x_1;x_2\), pt (2) có 2 nghiệm \(x_3;x_4\) thỏa :
\(x_3-x_1=x_4-x_2=1\)
giải pt bằng cách đặt ẩn phụ:
a) \(x^3+\sqrt{\left(1-x^2\right)^3}=x\sqrt{\left(2-2x^2\right)}\)
b) \(\frac{9-2x}{\sqrt{\left(4-x\right)}}+\frac{4x+3}{\sqrt{\left(4x+1\right)}}=\frac{15}{2}\)
c) \(\sqrt[3]{\left(7-16x\right)}+2\sqrt{\left(2x+8\right)}=5\)
d) \(5\sqrt{\left(x+1\right)}-2\sqrt[3]{\left(7x+6\right)}=4\)
2. Giải PT:
a) \(\frac{9x-7}{\sqrt{7x+5}}=\sqrt{7x+5}.\)
b) \(\sqrt{4x-20}+3\sqrt{\frac{x-5}{9}}-\frac{1}{3}\sqrt{9x-45}=4.\)
c) \(2x-x^2+\sqrt{6x^2-12x+7}=0.\)
d) \(\left(x+1\right)\left(x+4\right)-3\sqrt{x^2+5x+2}=6.\)
cho pt : \(3x^2-4x-8=0\)
a) Chứng minh pt có 2 nghiệm phân biệt
b) Không giải pt hãy tính: A= \(\left(x_1-1\right)x_1+\left(x_2-1\right)x_2\) B=\(x^2_1x^2_2-\left(x_1-x_2\right)^2\)
C= \(2x^2_1+2x^2_2-x^2_1x_2-x^2_2x_1\)
B1:Giải bpt sau:\(\left(\sqrt{13}-\sqrt{2x^2-2x+5}-\sqrt{2x^2-4x+4}\right).\left(x^6-x^3+x^2-x+1\right)\ge0\)
B2:Cho a;b;c>0 thỏa mãn \(a+b+c=\frac{1}{a}+\frac{1}{b}+\frac{1}{c}\).CMR \(3\left(a+b+c\right)\ge\sqrt{8a^2+1}+\sqrt{8b^2+1}+\sqrt{8c^2+1}\)
B3:giải pt nghiệm nguyên sau : \(6\left(y^2-1\right)+3\left(x^2+y^2z^2\right)+2\left(z^2-9x\right)=0\)
1)\(7\sqrt{3x-7}+\left(4x-7\right)\sqrt{7-x}=32\)
2)\(4x^2-11x+6=\left(x-1\right)\sqrt{2x^2-6x+6}\)
3)\(9+3\sqrt{x\left(3-2x\right)}=7\sqrt{x}+5\sqrt{3-2x}\)
4)\(\sqrt{2x^2+4x+7}=x^4+4x^3+3x^2-2x-7\)
5)\(\frac{6-2x}{\sqrt{5-x}}+\frac{6+2x}{\sqrt{5+x}}=\frac{8}{3}\)
6)\(2\left(5x-3\right)\sqrt{x+1}+\left(x+1\right)\sqrt{3-x}=3\left(5x+1\right)\)
7)\(\sqrt{7x+7}+\sqrt{7x-6}+2\sqrt{49x^2+7x-42}=181-14x\)
Ai dậy r giúp vs :33 1 câu cx đc nhé :v toàn giải pt hết nhé
1) \(4x^2+\left(8x-4\right)\sqrt{x}-1=3x+2\sqrt{2x^2+5x-3}.\)
2) \(\left(5x+8\right)\sqrt{2x-1}+7x\sqrt{x+3}=9x+18-\left(x+26\right)\sqrt{x-1}\)
3) \(\sqrt[3]{3x+1}+\sqrt[3]{5-x}+\sqrt[3]{2x-9}-\sqrt[3]{4x-3}=0\)
4) \(\left(x+17\right)\sqrt{4-x}+\left(20-x\right)\sqrt{x+1}-9\sqrt{4-x}.\sqrt{x+1}=36\)
help me now
\(\left(x-x^2\right)\left(\sqrt{x-2}+2\right)=2x^3-5x^2+5x-2\)
\(\sqrt{2x-3+\sqrt{4x-7}}+\sqrt{2x+9+5\sqrt{4x-7}}=4\sqrt{2}\)
\(\left(\sqrt{3x+1}-\sqrt{x+2}\right)\left(\sqrt{3x^2+7x+2}+9\right)=6x-3\)
Giai pt
1) \(\left(x+5\right)\left(2-x\right)=3\sqrt{x^2+3x}\)
2) \(\frac{x}{x+1}-2\sqrt{\frac{x+1}{x}}-3=0\)
3) \(x^2+\sqrt{2x^2+4x+3}=6-2x\)
4) \(x^2+\sqrt{x+5}=5\)
5) \(x^3+4x-\left(2x+7\right)\sqrt{2x+3}=0\)
