(2x+1)(3x2-2x+2)giai nhanh giup em
a2-2ab+b2-9
x2+2x+1-y2
25-x2-2xy-y2 giai nhanh giup em,com on
1) \(a^2-2ab+b^2-9=\left(a-b\right)^2-9=\left(a-b-3\right)\left(a-b+3\right)\)
2) \(x^2+2x+1-y^2=\left(x+1\right)^2-y^2=\left(x+1-y\right)\left(x+1+y\right)\)
3) \(25-x^2-2xy-y^2=25-\left(x+y\right)^2=\left(5-x-y\right)\left(5+x+y\right)\)
\(1,=\left(a-b\right)^2-9=\left(a-b-3\right)\left(a-b+3\right)\\ 2,=\left(x+1\right)^2-y^2=\left(x-y+1\right)\left(x+y+1\right)\\ 3,=25-\left(x+y\right)^2=\left(5-x-y\right)\left(5+x+y\right)\)
giai giup em nha
tim x biet (2x+1)+ (2x+2)...+(2x+2015)=0
tìm x
(2x+1) + (2x+2) + (2x+3) +.....+ (2x+2015) = 0
=> 2015.2x + (1+2+3+...+2015) = 0
=> 4030x + 2031120 = 0
=> 4030x = -2031120
=> x = -504
Ta có: (2x + 1) + (2x + 2) + (2x + 3) +.....+ (2x + 2015) = 0
<=> (2x + 2x + 2x + ..... + 2x) + (1+2+3+...+2015) = 0
<=> 4030x + 2031120 = 0
=> 4030x = -2031120
=> x = -2031120 : 4030
=> x = -504
Câu 1 Thực hiện phép tính :
a) 2x( 3x2 - 4x + 2 )
b) 2x( 3x + 5 ) - 3 ( 2x2 - 2x + 3 )
GIẢI NHANH HỘ EM Ạ
Lời giải:
a.
$2x(3x^2-4x+2)=2x.3x^2-2x.4x+2x.2$
$=6x^3-8x^2+4x$
b.
$2x(3x+5)-3(2x^2-2x+3)=2x.3x+2x.5-(3.2x^2-3.2x+3.3)$
$=6x^2+10x-6x^2+6x-9=16x-9$
bai 1 tinh
a)(x+3)^2
b)(2x+1)^2-(2x+3)(2x-3) giup em nhanh nhe
a) \(=x^2+6x+9\)
b) \(=4x^2+4x+1-4x^2+9=4x+10\)
a) \(\left(x+3\right)^2=x^2+6x+9\)
b) \(\left(2x+1\right)^2-\left(2x+3\right)\left(2x-3\right)=4x^2+4x+1-4x^2+9\)
\(=4x+10\)
(3x4 +x3-7x2-2x+2) : (3x2+x-1) tính giup mik với
f) -3-2x = 1-x
g) -5-3x = 11-2x
giai nhanh giup minh minh se tick cho nha
giải phương trình
\(\left(\sqrt{2x+3}-\sqrt{x+1}\right)\left(\sqrt{2x^2+5x+3}+1\right)\)=x+2
giai giup em voi em can gap
Có \(2x^2+5x+3=2x^2+2x+3x+3=2x\left(x+1\right)+3\left(x+1\right)=\left(x+1\right)\left(2x+3\right)\)
\(\Rightarrow\left(\sqrt{2x+3}-\sqrt{x+1}\right)\left(\sqrt{2x^2+5x+3}+1\right)=x+2\left(ĐKXĐ:x\ge-1\right)\\ \Leftrightarrow\left(\sqrt{2x+3}-\sqrt{x+1}\right)\left(\sqrt{\left(2x+3\right)\left(x+1\right)}+1\right)=2x+3-\left(x+1\right)\left(1\right)\)
Đặt \(\sqrt{2x+3}=a\ge1,\sqrt{x+1}=b\ge0\), phương trình (1) trở thành:
\(\left(a-b\right)\left(ab+1\right)=a^2-b^2\)
\(\left(a-b\right)\left(ab+1\right)-\left(a-b\right)\left(a+b\right)=0\\ \Leftrightarrow\left(a-b\right)\left(ab+1-a-b\right)=0\\ \Leftrightarrow\left(a-b\right)\left[a\left(b-1\right)-\left(b-1\right)\right]=0\\ \Leftrightarrow\left(a-b\right)\left(a-1\right)\left(b-1\right)=0\\
\Leftrightarrow\left[{}\begin{matrix}a-b=0\\a-1=0\\b-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}a=b\\a=1\\b=1\end{matrix}\right.\)
+) Với a=b ta có: \(\sqrt{2x+3}=\sqrt{x+1}\Leftrightarrow2x+3=x+1\Leftrightarrow x=-2\left(ktm\right)\)
+) Với a=1 ta có: \(\sqrt{2x+3}=1\Leftrightarrow2x+3=1\Leftrightarrow x=-1\left(tm\right)\)
+) Với b=1 ta có : \(\sqrt{x+1}=1\Leftrightarrow x+1=1\Leftrightarrow x=0\left(tm\right)\)
Vậy phương trình có tập nghiệm \(S=\left\{-1;0\right\}\).
Tick cho mình nha <3 !!!
Tim x biet :
7x+2 +7x+1+7 /57 = 52x +52x+1+52x+3 /131
Nhanh tay giai giup to di may than dong toan oi
\(\frac{x-4}{2015}-\frac{1}{2015}=\frac{10-2x}{2015}\)
Giai nhanh giup to!
bài dễ z mà k hỉu hả, mẫu số = nhau thi tử số = nhau,