Question

(a+3)*(a-3)= (5+d)*(5-d)=(x+1)*(1-x)=(2a+b)*(2a-b)=(a-3b)*(3b+a)=(2m-3n)*(2m+3n)=​

Answer 1

Ответ:

(a+3)•(a-3)=3а•(-2а)=-6a

(5+d)•(5-d)=5d•4d=20d

(x+1)•(1-x)=x•x=x

(2a+b)•(2a-b)=(2a+2a)•(b-b)=4a•b

(a-3b)•(3b+a)=(3b-3b)•(a+a)=b•2a

(2m-3n)•(2m+3n)=(2m+2m)•(3n-3n)=4m•n

Answer 2

Let's expand each of the given expressions:

1. (a + 3)(a - 3): Using the difference of squares formula (a^2 - b^2 = (a + b)(a - b)): (a + 3)(a - 3) = a^2 - 3^2 = a^2 - 9

2. (5 + d)(5 - d): Using the difference of squares formula: (5 + d)(5 - d) = 5^2 - d^2 = 25 - d^2

3. (x + 1)(1 - x): This expression also involves the difference of squares: (x + 1)(1 - x) = 1^2 - x^2 = 1 - x^2

4. (2a + b)(2a - b): Again, we can use the difference of squares formula: (2a + b)(2a - b) = (2a)^2 - b^2 = 4a^2 - b^2

5. (a - 3b)(3b + a): We can use the difference of squares formula once more: (a - 3b)(3b + a) = (a)^2 - (3b)^2 = a^2 - 9b^2

6. (2m - 3n)(2m + 3n): Using the difference of squares formula: (2m - 3n)(2m + 3n) = (2m)^2 - (3n)^2 = 4m^2 - 9n^2

So, the expanded expressions are as follows:

1. (a + 3)*(a - 3) = a^2 - 9
2. (5 + d)*(5 - d) = 25 - d^2
3. (x + 1)*(1 - x) = 1 - x^2
4. (2a + b)*(2a - b) = 4a^2 - b^2
5. (a - 3b)*(3b + a) = a^2 - 9b^2
6. (2m - 3n)*(2m + 3n) = 4m^2 - 9n^2