4)

a,

\(34^2+66^2+68\cdot66\\ =34^2+68\cdot66+66^2\\=34^2+2\cdot34\cdot68+66^2\\ =\left(34+66\right)^2\\ =100^2 =10000\)

b,

\(74^2+24^2-48\cdot74\\ =74^2-48\cdot74+24^2\\ =74^2-2\cdot24\cdot74+24^2\\ =\left(74-24\right)^2\\ =50^2=2500\)

c,

\(729^2-728^2\\ =\left(729+728\right)\left(729-728\right)\\ =1457\cdot1\\ =1457\)

d,

\(1001^2-1\\ =1001^2-1^2\\ =\left(1001+1\right)\left(1001-1\right)\\ =1002\cdot1000\\ =1002000\)

5)

a,

\(\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\\ =1\cdot\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\\ =\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\\ =\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\\ =\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\\ =\left(2^8-1\right)\left(2^8+1\right)\\ =2^{16}-1\)

b,

\(7\cdot\left(2^3+1\right)\left(2^6+1\right)\left(2^{12}+1\right)\left(2^{24}+1\right)\\ =\left(2^3-1\right)\left(2^3+1\right)\left(2^6+1\right)\left(2^{12}+1\right)\left(2^{24}+1\right)\\ =\left(2^6-1\right)\left(2^6+1\right)\left(2^{12}+1\right)\left(2^{24}+1\right)\\ =\left(2^{12}-1\right)\left(2^{12}+1\right)\left(2^{24}+1\right)\\ =\left(2^{24}-1\right)\left(2^{24}+1\right)\\ =2^{48}-1\)

a. 34^2 + 66^2 + 68 x 66

= 34 x 34 + 66 x 66 + 68 x 66

= 34 x 34 + 66 x (66 + 68)

= 34 x 34 + 66 x 134

= 34 x 34 + 66 x 34 + 66 x 100

= 34 x (34 + 66) + 66 x 100

= 34 x 100 + 66 x 100

= (34 + 66) x 100

= 100 x 100

= 10000

\(34^2+66^2+68.66\)

\(=34.34+66.66+68.66\)

\(=34.34+66.\left(68+66\right)\)

\(=34.34+66.134\)

\(=34.34+66.\left(100+34\right)\)

\(=34.34+66.100+66.34\)

\(=34.\left(66+34\right)+66.100\)

\(=34.100+66.100\)

\(=\left(34+66\right).100\)

\(=100^2\)

\(=10000\)

( 34^2+66^2+68.66

= 34^2 + 66^2 + 2. 34.66

= ( 34+66)^2

= 100^2 = 10 000

b) 74^2 + 24^2 - 48.74

= 74^2 + 24^2 - 2. 74 . 24

= (74-24)^2 = 50^2 = 2500 

a) 34^2 + 66^2 + 68 . 66 = 5580,66

b) 74^2 + 24^2 – 48 . 74 = 6003.26 

a, = 34^2 + 66^2 + 2.34.66

    = (34+66)^2 = 100^2 = 10000

b, = 74^2+24^2-2.24.74

   = (74-24)^2 = 500^2 = 250000

Tk mk nha

a/ 34^2 + 66^2 + 68 . 66

=34²+2.34.66+66²

=(34+66)²

=100²

=10000

b/ 74^2 + 24^2 - 48 . 74

=74²-2.74.24+24²

=(74-24)²

=50²

=2500

\(a,34^2+66^2+68.66\)

\(=34^2+2.34.66+66^2\)

\(=\left(34+66\right)^2\)

\(=100^2\)

\(=10000\)

\(b,74^2+24^2-48.74\)

\(=74^2-2.74.24+24^2\)

\(=\left(74-24\right)^2\)

\(=50^2\)

\(=2500\)

a) \(34^2+66^2+68.66\)

\(=34^2+2.34.66+66^2\)

\(=\left(34+66\right)^2\)

\(=100^2=10000\)

b)  \(74^2+24^2-48.74\)

\(=74^2-2.74.24+24^2\)

\(=\left(74-24\right)^2\)

\(=50^2=2500\)

`a)1001^2`

`=(1000+1)^2=1000000+2000+1`

`=1002001`

`b)29,9.30,1`

`=(30-0,1)(30+0,1)`

`=30^2-0,1^2`

`=900-0,01=899,99`

`c)199^2=(200-1)^2`

`=40000-400+1`

`=39601`

`d)84^2-16^2`

`=(84-16)(84+16)`

`=100.68`

`=6800`

`e)313^2-312^2`

`=(313-312)(313+312)`

`=625`

`f)47.53`

`=(50-3)(50+3)`

`=2500-9=2491`