b=(15x3^2-16:2^2)x(3+3^2+3^3+3^4+...+362007)x(36x333-111x108)
[2+4+6+ ....+240] x x[111x108-36x333] = ?
Tính nhanh
a) 19x64 + 76 x 34
b) 35 x 12 + 65 x13
c) 136 x 68 + 16 x 272
d) ( 2 + 4 + 6 +.........+100) x (36x333 - 108 x111)
e) 1 + 2 + 3 + 4 +........+19 + 20
f) 1 + 3 + 5 +.......+ 17 + 19
g) 2 + 4 + 6 +.........+ 18 + 20
CÁC BẠN NÀO NHÌN THẤY THÌ GIẢI GIÚP MK NHA. MK ĐANG CẦN GẤP BÀI NÀY. CHO MK CẢ CÁCH GIẢI NHA.
a) 19 x 64 + 76 x 34
= 19 x 64 + 19 x 136
= 19.(64 + 136)
= 19 . 200
= 3800
a) 19 x 64 + 76 x 34
= 19 x 64 + 19 x 136
= 19.(64 + 136)
= 19 . 200
= 3800
`#040911`
a,
\(\dfrac{1}{2}\cdot\left(x-4\right)-\dfrac{1}{4}\cdot\left(x-\dfrac{4}{3}\right)=2\cdot\left(x-\dfrac{1}{2}\right)\)
\(\Rightarrow\dfrac{1}{2}x-2-\dfrac{1}{4}x+\dfrac{1}{3}=2x-1\\\Rightarrow\left(\dfrac{1}{2}x-\dfrac{1}{4}x-2x\right)=2-\dfrac{1}{3}-1\\ \Rightarrow-\dfrac{7}{4}x=\dfrac{2}{3}\\ \Rightarrow x=\dfrac{2}{3}\div\left(-\dfrac{7}{4}\right)\\ \Rightarrow x=-\dfrac{8}{21}\)
Vậy, \(x=-\dfrac{8}{21}\)
b,
\(\dfrac{3}{4}-\left(x-\dfrac{1}{2}\right)^2=-\dfrac{11}{2}\)
\(\Rightarrow\left(x-\dfrac{1}{2}\right)^2=\dfrac{3}{4}-\left(-\dfrac{11}{2}\right)\\ \Rightarrow\left(x-\dfrac{1}{2}\right)^2=\dfrac{25}{4}\\ \Rightarrow\left(x-\dfrac{1}{2}\right)^2=\left(\pm\dfrac{5}{2}\right)^2\)
\(\Rightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{5}{2}\\x-\dfrac{1}{2}=-\dfrac{5}{2}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{5}{2}+\dfrac{1}{2}\\x=-\dfrac{5}{2}+\dfrac{1}{2}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\)
Vậy, \(x\in\left\{-2;3\right\}\)
c,
\(\dfrac{3}{16}+1\dfrac{1}{16}\cdot\left(x-\dfrac{2}{3}\right)^2=\dfrac{3}{4}\)
\(\Rightarrow\dfrac{17}{16}\cdot\left(x-\dfrac{2}{3}\right)^2=\dfrac{3}{4}-\dfrac{3}{16}\\ \Rightarrow\dfrac{17}{16}\cdot\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{16}\\ \Rightarrow\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{16}\div\dfrac{17}{16}\\ \Rightarrow\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{17}\)
Bạn xem lại đề có sai kh nhỉ?
c) \(\dfrac{3}{16}+\dfrac{1}{\dfrac{1}{16}}\left(x-\dfrac{2}{3}\right)^2=\dfrac{3}{4}\)
\(\Rightarrow16\left(x-\dfrac{2}{3}\right)^2=\dfrac{3}{4}-\dfrac{3}{16}\)
\(\Rightarrow16\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{16}\)
\(\Rightarrow\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{16}:16\)
\(\Rightarrow\left(x-\dfrac{2}{3}\right)^2=\dfrac{9}{256}=\left(\dfrac{3}{16}\right)^2\)
\(\Rightarrow\left[{}\begin{matrix}x-\dfrac{2}{3}=\dfrac{3}{16}\\x-\dfrac{2}{3}=-\dfrac{3}{16}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{16}+\dfrac{2}{3}\\x=-\dfrac{3}{16}+\dfrac{2}{3}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{41}{48}\\x=\dfrac{23}{48}\end{matrix}\right.\)
(2+4+6+...+2020-1-3-5-....-2019)x(36x333-108x111)
giúp mih với ai nhanh mik tích cho
(2+4+6+...+100).(36.333−108.111)=(2+4+6+...+100).(36.333−108.111)=(2+4+6+...+100).(36.3.111−36.3.111)(2+4+6+...+100).(36.3.111−36.3.111)=(2+4+6+...+100).0=(2+4+6+...+100).0=0
= 0 NHÉ BẠN
a ) 3^6 : 3^4 + 2^2x(12-3^3) - 2^0
b) 5^3 x 52 + 5^3 x7 - 5^3
c) 5^3 + ( 4 + 3^4) x2 + (3^3 - 3 ) : 4
d) (2x25x7 - 21x15) : 7
e) 5 x [(92+ 2^5 : 2^2 ) : 5^2 + 2^4 ] - 7^2
f ) ( 5^16 + 4^16) x 3^17 - 3^10 ) x ( 2^4 - 4^2 )
1,Tìm x, biết:
a, |x|+1/3=4/5
b, |x+2/3|=1/4
c, |x-3/4|-2/3=3/5
d, 1/4+2.|2/3-x|=3/4
e, 16^x:4^x=16
g, (2x+1)^3=-64
h, 2^x/2+4.2^x=72
2,Tính
A=(1/2-1).(1/3-1).(1/4-1).....(1/2015-1)
B=1/1.2+1/2.3+1/3.4+...+1/2014.2015
a, 2.x.(x-1)^2-3.x.(x+3).(x-3)-4.x.(x+1)^2
b,(a-b+c)^2-(b-c)^2+2.a.b-2.a.c
c,(3.x+1)^2-2.(1+3.x).(3.x+5)+(3.x+5)^2
d, (3+1).(3^2+1).(3^4+1).(3^8+1).(3^16+1).(3^32+1)
e, (a+b-c)^2+(a-b+c)^2+(b-c-a)^2+(c-a-b)^2
bai 166 a) 6x^2 -11x +3 phan tich cac da thuc sau thanh nhan tu
b) 2x^+3x-27
c) 2x^2-5xy-3y^2
bai 167 a) x^3+2x-3 b) x^3-7x+6 c)x^3 +5x^2 +8x +4 d) x^3 -9x^2 +6x +16
e)x^3-x^2-x-2 g ) x^3+x^2-x+2 h)x^3 -6x^2-x+30
bai 169 a) 27x^3-27x^2 +18x-4
b)2x^3-x^2+5x+3
c)(x^2-3)^2+16
Dài 166
b) 2x2+3x-27=2x2-6x+9x-27=2x(x-3)+9(x-3)=(x-3)(2x+9)
bài 1 rút gọn biểu thức
a) (2x-5)^2-4x(x+3)
b) (x-2)^3 -6(x+4)(x-4)-(x-2)(x^2+2x+4)
c)(x-1)^2-2(x-1)(x+2)+(x+2)^2+5(2x-3)
bài 2 rút gọn biểu thức
a)(2-3x)^2-5x(x-4)+4(x-1)
b)(3-x)(x^2+3x+9)+(x-3)^3
c)(x-4)^2(x+4)-(x-4)(x+4)^2+3(x^2-16)
1:
a: \(\left(2x-5\right)^2-4x\left(x+3\right)\)
\(=4x^2-20x+25-4x^2-12x\)
=-32x+25
b: \(\left(x-2\right)^3-6\left(x+4\right)\left(x-4\right)-\left(x-2\right)\left(x^2+2x+4\right)\)
\(=x^3-6x^2+12x-8-\left(x^3-8\right)-6\left(x^2-16\right)\)
\(=-6x^2+12x-6x^2+96=-12x^2+12x+96\)
c: \(\left(x-1\right)^2-2\left(x-1\right)\left(x+2\right)+\left(x+2\right)^2+5\left(2x-3\right)\)
\(=\left(x-1-x-2\right)^2+5\left(2x-3\right)\)
\(=\left(-3\right)^2+5\left(2x-3\right)\)
\(=9+10x-15=10x-6\)
2:
a: \(\left(2-3x\right)^2-5x\left(x-4\right)+4\left(x-1\right)\)
\(=9x^2-12x+4-5x^2+20x+4x-4\)
\(=4x^2+12x\)
b: \(\left(3-x\right)\left(x^2+3x+9\right)+\left(x-3\right)^3\)
\(=27-x^3+x^3-9x^2+27x-27\)
\(=-9x^2+27x\)
c: \(\left(x-4\right)^2\left(x+4\right)-\left(x-4\right)\left(x+4\right)^2+3\left(x^2-16\right)\)
\(=\left(x-4\right)\left(x+4\right)\left(x-4-x-4\right)+3\left(x^2-16\right)\)
\(=\left(x^2-16\right)\left(-8\right)+3\left(x^2-16\right)\)
\(=-5\left(x^2-16\right)=-5x^2+80\)