98.28-(184-1)(184+1)

=98.28-\(184^2\)+1

=2744-33856 +1

=-31111

98.28-(184-1)(184+1)

=2744-183.185

=2744-33855

=-31111

\(Bài.1:\\ a,104^2-16=104^2-4^2=\left(104+4\right)\left(104-4\right)=108.100=10800\\ b,9^8.2^8-\left(18^4-1\right)\left(18^4+1\right)\\ =\left(9.2\right)^8-\left(18^8-1\right)=18^8-18^8+1=1\\ c,999^3+3.999^2+3.999+1\\ =999^3+3.999^2.1+3.999.1^2+1^3=\left(999+1\right)^3=1000^3=1000000000\\ d,42^3-6.42^2+12.42-8\\ =42^3-3.42^2.2+3.42.2^2-2^3\\ =\left(42-2\right)^3=40^3=64000\)

Bài 1

a) 104² - 16

= 104² - 4²

= (104 - 4)(104 + 4)

= 100.108

= 10800

b) 9⁸.2⁸ - (18⁴ - 1)(18⁴ + 1)

= 18⁸ - (18⁸ - 1)

= 18⁸ - 18⁸ + 1

= 1

c) 999³ + 3.999² + 3.999 + 1

= (999 + 1)³

= 1000³

= 1000000000

d) 42³ - 6.42² + 12.42 - 8

= (42 - 2)³

= 40³

= 64000

Bài 2

a) x(x - 2012) - 2013x + 2012.2013 = 0

⇔ x(x - 2012) - 2013(x - 2012) = 0

⇔ (x - 2012)(x - 2013) = 0

⇔ x - 2012 = 0 hoặc x - 2013 = 0

*) x - 2012 = 0

⇔ x = 2012

*) x - 2013 = 0

⇔ x = 2013

Vậy x = 2012; x = 2013

b) (x - 1)³ + 1 + 3x(x - 4) = 0

⇔ x³ - 3x² + 3x - 1 + 1 + 3x² - 12x = 0

⇔ x³ - 9x = 0

⇔ x(x² - 9) = 0

⇔ x(x - 3)(x + 3) = 0

⇔ x = 0 hoặc x - 3 = 0 hoặc x + 3 = 0

*) x - 3 = 0

⇔ x = 3

*) x + 3 = 0

⇔ x = -3

Vậy x = -3; x = 0; x = 3

c) (x + 4)² - 16 = 0

⇔ (x + 4)² - 4² = 0

⇔ (x + 4 - 4)(x + 4 + 4) = 0x

⇔ (x + 8) = 0

⇔ x = 0 hoặc x + 8 = 0

*) x + 8 = 0

⇔ x = -8

Vậy x = -8; x = 0

a) \(=\left(127+73\right)^2=200^2=40000\)

b) \(=18^8-\left(18^8-1\right)=1\)

c) \(=\left(100+99\right)\left(100-99\right)+\left(98+97\right)\left(98-97\right)+...+\left(2+1\right)\left(2-1\right)\)

\(=100+99+98+97+...+2+1=5050\)

d) biến đổi thành \(20^2-19^2+18^2-17^2+..+2^2-1^2\)

rồi giải ra như trên

\(a.x^3+8-x^3+2=10\)

\(b.x^2+10x+25-4x\left(4x^2+12x+9\right)-\left(2x-1\right)\left(x^2-9\right)=x^2+10x+25-16x^3-28x^2-36x-2x^3+18x+x^2-9=-18x^3-26x^2-8x+16=\)

Bài 1:

a. 

$=(x^3+2^3)-(x^3-2)=2^3+2=10$

b.

$=(x^2+10x+25)-4x(4x^2+12x+9)-(2x-1)(x^2-9)$
$=x^2+10x+25-16x^3-48x^2-36x-(2x^3-18x-x^2+9)$

$=-18x^3-46x^2-8x+16$

2.

a. 

$301^2=(300+1)^2=300^2+2.300+1=90000+600+1$

$=90601$

b.

$198^2=(200-2)^2=4(100-1)^2=4(100^2-2.100+1)$

$=4(10000-200+1)=4.9801=39204$

c.

$93.107=(100-7)(100+7)=100^2-7^2$

$=10000-49=9951$

d.

$127^2+146.127+73^2$

$=127^2+2.73.127+73^2$
$=(127+73)^2=200^2=40000$