Помогите срочно.
9. упростите
1.(3-x)2
2.(4x-6)2
3.(m-6)(m+6)
4.(m2 + 3n)(m2-3n)

1) (3-x)²=9+x²-6x

2) (4x-6)²=16x²+36-48x

3) (m-6)(m+6)=m²-36

4) (m²+3n)(m²-3n)=m⁴-9n²

1.

(3-x)²  = 3² - 2*3*х - х² = 9 - 6х + х²,

2.

(4x-6)²  = (4х)² - 2*4х*6 + 6² = 16х² - 48х + 36,

3.

(m-6)(m+6)  = m² - 6² = m² - 36,

4.

(m² + 3n)(m²-3n) = (m²)² - (3n)² = m⁴ - 9n²