Question

Упростить выражение 1) (a-4)(a+9)-a(1-2a) 2) (c+2)(c-3)-(c-1)^2

Answer 1

В дискриминанте получается корень из 1936=44

Answer 2

1. (a - 4)(a + 9) - a(1 - 2a)

First, let's simplify the expression step by step:

Expanding the first set of parentheses: (a * a + a * 9 - 4 * a - 4 * 9) - a(1 - 2a)

Simplifying inside the parentheses: (a^2 + 9a - 4a - 36) - a(1 - 2a)

Combining like terms: (a^2 + 5a - 36) - a(1 - 2a)

Distributing the negative sign inside the second set of parentheses: (a^2 + 5a - 36) - (a - 2a^2)

Expanding the second set of parentheses: (a^2 + 5a - 36) - (a - 2a^2) = a^2 + 5a - 36 - a + 2a^2

Combining like terms: 3a^2 + 4a - 36 - a = 3a^2 + 3a - 36

Therefore, the simplified expression is 3a^2 + 3a - 36.

2. (c + 2)(c - 3) - (c - 1)^2

Expanding the first set of parentheses: (c * c + c * (-3) + 2 * c + 2 * (-3)) - (c - 1)^2

Simplifying inside the parentheses: (c^2 - 3c + 2c - 6) - (c - 1)^2

Combining like terms: (c^2 - c - 6) - (c^2 - 2c + 1)

Removing the parentheses by distributing the negative sign: c^2 - c - 6 - c^2 + 2c - 1

Combining like terms:

• c - 6 + 2c - 1 = c + 2c - c - 6 - 1

Combining like terms again: 2c - 7

Therefore, the simplified expression is 2c - 7.