x² = 361

=> x² = 19²

=> x = 19

Tick mik nhé !!!

19 mu 2

\(\left\{315-\left[\left(60-41\right)^2-361\right]\cdot4217\right\}+2885\)    

\(=\left[315-\left(19^2-361\right)\cdot4217\right]+2885\)    

\(=\left[315-\left(361-361\right)\cdot4217\right]+2885\)   

\(=\left(315-0\cdot4217\right)+2885\)    

\(=\left(315-0\right)+2885\)   

\(=315+2885\)    

\(=3200\)

\(\left\{315-[\left(60-41\right)^2-361]\times4217\right\}+2885\)

\(=\left\{315-[19^2-361]\times4217\right\}+2885\)

\(=\left\{315-0\times4217\right\}+2885\)

\(=315+2885\)

\(=3200\)

169 = 13²

256 = 2⁸

361 = 19²

`361=19^2`

19²

Ta có: 2421 x 2 = 4842

            361 x 1 = 361

Vậy  [?] = 1112 x 3 =3336

a/  763                          b/ 361 : 3    120 dư 1

a: =5-78*32

=5-2496

=-2491

b: \(=6\left(9-6\right)=6\cdot3=18\)

c: \(=46\cdot\dfrac{\left(123-42\right)}{81}=46\)

d: \(=181+3-84+8\cdot25\)

=100+200

=300

e: \(=64\cdot35+140\cdot84-1=2240-1+11760\)

=14000-1

=13999

f: \(=3^3+25\cdot8-1=26+200=226\)

g: \(=3+2^4+1=16+4=20\)

h: \(=36:4\cdot3+2\cdot25-1=27+50-1=27+49=76\)

1; 7³.5².5⁴.7⁶:(5⁵.7⁸)

= (7³.7⁶).(5².5⁴) : (5⁵.7⁸)

= 7⁹.5⁶: (5⁵.7⁸)

= (7⁹:7⁸).(5⁶:5⁵)

= 7.5

= 35

2; 3³.a⁷.3.a²:(3⁴.a⁶)

= (3³.3).(a⁷.a²): (3⁴.a⁶)

= 3⁴.a⁹: (3⁴.a⁶)

= (3⁴:3⁴).(a⁹:a⁶)

= a³