(x−1)(5x2−3x+2)=x(5x2−3x+2)−1(5x2−3x+2)

41. His efforts to find a solution didn’t deserve such savage criticism.
→ He shouldn’t ...............................................................................................
42. You have to clean all the glass windows every morning.
→ All the glass windows .................................................................................
43. The last time he met his mother was 6 months ago.
→ He ...............................................................................................................
44. It took them 2 weeks to repaint their house.
→ They spent ..................................................................................................
45. Mary is a good swimmer. She has won two gold medals.
→ Mary is .......................................................................................................

Với a,b,c thuộc R thỏa mãn : ${\left(3a+3b+3c\right)}^3=24+{\left(3a+b-c\right)}^3+{\left(3b+c-a\right)}^3+{\left(3c+a-b\right)}^3$

CMR : (a+2b)(b+2c)(c+2a)=1

Với a,b,c thuộc R thỏa mãn : (3a+3b+3c)3=24+(3a+b−c)3+(3b+c−a)3+(3c+a−b)3

CMR : (a+2b)(b+2c)(c+2a)=1

1+1=2