Question

Va rog cât de repede se poate!!

Answer 1

1)    2 ( 3 x + 1 ) + 3 ( 1 - 2 x ) = 6 x + 2 + 3 - 6 x = 5 

2) 3 ( x² - 2 x - 2)  + x ( 6 - 3 x ) = 3 x² - 6 x - 6 + 6 x - 3 x² = - 6 

3) x · x + x + x : x = x² + x + 1 = x ( x + 1 ) + 1 

4)   ( 2 √ 3 x )² : ( 3 x ²) = 4 · 3 x² : 3 x² = 4 

5)   x⁸ : x⁷ + x⁶ : x⁵ - x⁴ : x³ + x² : x = x ⁽⁸⁻⁷⁾ + x⁽ ⁶⁻⁵⁾ - x⁽⁴⁻³⁾ + x¹ = x + x - x + x = 2 x 

6)  ( x · x ²· x³ · x⁴) : x¹⁰ · x = x⁽¹⁰ ⁻¹⁰⁾ · x =x⁰ · x = 1 · x = x 

7)    ( x - 2) ( x + 2) + 4 = x² - 4 + 4 = x² 

8)  ( x - 3)(x + 3) - ( x + 3)² + 3 ( 2 x + 7) = x² - 9 - x² - 6 x - 9 + 6 x + 21 = 
= - 18 + 21 = 3 

9) ( x + 4 ) ( x - 3 ) - x + 12 = x² + 4 x - 3 x - 12 - x + 12 = x² + 4 x - 4 x = x² 

10 ) x² - 7 x + 5 - ( x + 8 ) ( x - 1) = x² - 7 x + 5 - ( x² + 8 x - x - 8 ) = 
x² - 7 x + 5 - x² - 7 x + 8 = - 14 x + 13 

11)  ( 2 x + 1)² - ( 2 x - 1)² = 4 x² + 4 x + 1 - ( 4 x² - 4 x + 1) =
=  4 x² + 4 x + 1 - 4 x² + 4 x - 1 = 8 x 

12) ( √x+1 + 1)² + ( √x+1 - x )² = x + 1 + 2 x √x+1 + x² +x + 1 - 2 x √ x+1 + x²
= 2 x² + 2 x + 2 = 2 ( x² + x + 1) 

13)  ( x² + x + 1 )² - ( x² + x)² =  ( x² + x + 1 - x² - x) (  x² + x + 1 + x² + x) =
= 2 x² + 2 x + 1