a+b=-m; b+m=-a; a+m=-b

A=(a+b)/b*(m+b)/m*(m+a)/a=-1

k) 10 (24-3x):15=250-244

10(24-3x):15=6

10(24-3x)=6.15

10(24-3x)=90

24-3x=90:10

24-3x=9

3x=24-9

3x=15

x=15:3=5

5.3²-32:4²

^=5.9-32:16

^=45-2=43

A= x2-20x+101

= x2-20x+100+1

= (x²-20x+100)+1

= (x-10)²+1

do (x-10)² ≥ 0 ∀ x

⇔ (x-10)²+1 ≥ 1 ∀ x

⇔ A ≥ 1 ∀ x

=> min A =1 khi x=10

B= x²-4xy+5y²+10x-22y+28

= (x²-4xy+4y²)+ (10x+20y) +25+(y²+2y+1)+2

= [(x-2y)²+10(x-2y)+25]+(y+1)²+2

= (x-2y+5)²+(y+1)²+2

do (x-2y+5)² ≥ 0∀ x;y

(y+1)² ≥ 0∀ y

=> (x-2y+5)² + (y+1)² ≥ 0∀ x;y

⇔ (x-2y+5)²+(y+1)²+2 ≥ 2∀ x;y

⇔ B ≥ 2∀ x;y

min B =2 khi y=-1;x=-3

1A(adj)

2D(n)

3A(adj)

4C(n)

5D(adj)

6C(adj)

7B(n)(Tham khảo c7)

8A(n)

9C(n)

10B(v)

11A(adv)

mik cx chẳng bt

mik bt

1.Has

2.catches

3.reaches

4.does

5.enjoys

6.washes