a: =75^2-2*75*25+25^2

=(75-25)^2=50^2=2500

b: =(100-3)(100+3)

=100^2-9

=10000-9

=9991

\(75^2+25^2-50.75\)

\(=75^2-2.25.75+25^2\)

\(=\left(75-25\right)^2\)

\(=50^2\)

\(=2500\)

\(75.\left(25-52\right)-52.\left(25-75\right)\)

\(=75.25-75.52-52.25+52.75\)

\(=25.\left(75-52\right)\)'

\(=25.23=575\)

75.(25-52)-52.(25-75)

=75.25-75.52-52.25-52.75

=...tự làm đi

Bài 2: Tính nhanh

a) 29 + 132 + 237 + 868 + 3

 = 29+(132+858)+(237+3)

=29+990+240

=1259

hình như bạn làm sai á

a: \(2004^2-16=2000\cdot2008=4016000\)

b: \(892^2+892\cdot216+108^2=1000^2=1000000\)

c: \(36^2-52\cdot36+26^2=10^2=100\)

a: \(2004^2-16\)

\(=\left(2004-4\right)\left(2004+4\right)=2000\cdot2008=4016000\)

b: \(892^2+892\cdot216+108^2\)

\(=892^2+2\cdot892\cdot108+108^2\)

\(=\left(892+108\right)^2=1000^2=1000000\)

c: \(36^2+26^2-52\cdot36\)

\(=36^2-2\cdot36\cdot26+26^2\)

\(=\left(36-26\right)^2=10^2=100\)

d: \(\left(10,2\cdot9,8-9,8\cdot0,2\right)+\left(10,22-10,2\cdot0,2\right)\)

\(=9,8\left(10,2-0,2\right)+10,22-2,04\)

=98+8,18

=106,18

e: \(20,03\cdot45+20,03\cdot47+20,03\cdot8\)

\(=20,03\cdot\left(45+47+8\right)\)

\(=20,03\cdot100=2003\)

g: \(15,75\cdot175-15,75\cdot55-15,75\cdot20\)

\(=15,75\cdot\left(175-55-20\right)\)

\(=15,75\cdot100=1575\)

h: \(A=57^2+114\cdot43+43^2\)

\(=57^2+2\cdot57\cdot43+43^2\)

\(=\left(57+43\right)^2=100^2=10000\)

i: \(B=5^4\cdot3^4-\left(15^2-1\right)\left(15^2+1\right)\)

\(=15^4-\left(15^4-1\right)=1\)

k: \(C=50^2-49^2+48^2-47^2+\cdots+2^2-1^2\)

\(=\left(50-49\right)\left(50+49\right)+\left(48-47\right)\left(48+47\right)+\cdots+\left(2-1\right)\left(2+1\right)\)

=50+49+...+2+1

\(=50\cdot\frac{51}{2}=25\cdot51=1225\)

Tính nhanh:

a; 1 + 3 + 9 + 27 + 6561 + 19683

= (27+ 3) + (9 + 6561) + (1 + 19683)

= 30 + 6570 + 19684

= 6600 + 19684

= 26284

876 - 42 - 76 + 242

= (876 - 76) + (242 - 42)

= 800 + 200

= 1000

nhiều quá mik chia ra giải nha

a) 1 + 2xy +x²y²

b) 25 + x² - y²

c) x⁴ - 1

d) sao giống câu c) vậy b

e) 8x³ + 36x² + 54x + 27

f) 27x³ - 27x² + 9x - 1

g) 64x³ - y³

h) 125a³ + 27b³

i), k) mik ko biết

thanks cậu