thiếu r

4,25 . 5 .20

=425

\(425\)

a) = (50-1)^2 = 50^2 - 2.50 + 1 = 2500 - 100 + 1 = 2401

b) = (50+1)^2 = 50^2 + 2.50 + 1 = 2601

c) = 9900

a) \(\left(-48\right)+10+\left(-22\right)+\left(-10\right)\)

\(=\left[\left(-48\right)+\left(-22\right)\right]+\left(-10+10\right)\)

\(=-70+0=-70\)

Tham khảo <3

= -70 

( hihi )

(-48)+(-22)+(10-10)

=-70 +0

=-70

\(a.75^2-50.75+25^2\\ =75^2-2.25.75+25^2\\ =\left(75-25\right)^2=50^2=2500\)

\(b.103.97\\ =\left(100+3\right)\left(100-3\right)\\ =100^2-3^2\\ =9991\)

\(a,75^2-50.75+25^2\\ =75^2-2.75.25+25^2\\ =\left(75+25\right)^2=100^2=10000\\ b,103.97\\ =\left(100+3\right).\left(100-3\right)\\ =100^2-3^2=10000-9=9991\)

a) \(75^2-2\cdot25\cdot75+25^2\)

= \(\left(75+25\right)^2\)

= \(100^2=10000\)
b) \(103\cdot97\)

= \(\left(100+3\right)\left(100-3\right)\)

= \(100^2-3^2\)

= \(10000-9=9991\)

làm giúp😢😢

a) 425.7.4-170.60

=85.5.7.4-85.2.60=85.(5.7.4-2.60)=85.20=1700

b) 8.9.14+6.17.12+19.4.18

=72.14+72.17+72.19=72.(14+17+19)=72.50=3600 

4996+2314+1003=8313

4996 + 2314 + 1003

= ( 4996 + 2314 ) + 1003

= 7310 + 1003

= 8313

4996+2314+1003=8313

Chúc bạn chăm ngoan học giỏi ,vâng lời ông bà , cha mẹ!!!.Kết bạn với mình nha!!!!!!!!!!!

a. Ta có: \(17^2-14.17+49=17^2-2.7.17+7^2=\left(17-7\right)^2=10^2=100\)

b. \(2021^2-2020^2=\left(2021-2020\right)\left(2021+2020\right)=4041\)

a) \(52^2\)

\(=\left(50+2\right)^2\)

\(=50^2+2\cdot2\cdot50+2^2\)

\(=2500+200+4\)

\(=2704\)

b) \(98^2\)

\(=\left(100-2\right)^2\)

\(=100^2-2\cdot100\cdot2+2^2\)

\(=10000-400+4\)

\(=9604\)

`a, 52^2 = (50+2)^2 = 2500 + 200 + 4 = 2704`

`b, 98^2  = (100-2)^2 = 100^2 - 2 . 100 . 2 + 4 = 10000 - 400 + 4`

`= 9604`

\(a,9\times435\times4+12\times565\times3\)

\(=36\times435+36\times565\)

\(=36\times\left(435+565\right)\)

\(=36\times1000\)

\(=36000\)

\(b,4\times1368\times21-7\times368\times12\)

\(=84\times1368-84\times368\)

\(=84\times\left(1368-368\right)\)

\(=84\times1000\)

\(=84000\)

TL

$a)9\times 435\times 4+12\times 565\times 3$

$=36\times 435+36\times 565$

$=36\times \left(435+565\right)$

$=36\times 1000$

$=36000$

$b)4\times 1368\times 21-7\times 368\times 12$

$=84\times 1368-84\times 368$

$=84\times \left(1368-368\right)$

$=84\times 1000$

$=84000$

$HT$