Question

A) (2a² - 3a +1) - (7a² - 5a);б) 3x(4x² - x);в)(x - 8)(x + 5);г) (x + 6)²

Answer 1

Ответ:

Объяснение:

а)2а²-3а+1-7a²+5a=-5a²+2a+1

б) 3х(4х²-х)=12х³-3х²

в)(х-8)(х+5)=х²-8х+5х-40=х²-3х-40

г) (х+6)²=х²+12х+36

Answer 2

Let's simplify the given expressions step by step:

a) (2a² - 3a + 1) - (7a² - 5a)

To simplify this expression, distribute the negative sign inside the second parentheses and then combine like terms:

(2a² - 3a + 1) - (7a² - 5a) = 2a² - 3a + 1 - 7a² + 5a = (2a² - 7a²) + (-3a + 5a) + 1 = -5a² + 2a + 1

So, the simplified expression is -5a² + 2a + 1.

b) 3x(4x² - x)

To simplify this expression, use the distributive property:

3x(4x² - x) = 3x * 4x² - 3x * x

Now, perform the multiplications:

= 12x³ - 3x²

The simplified expression is 12x³ - 3x².

в) (x - 8)(x + 5)

To simplify this expression, use the FOIL method (First, Outer, Inner, Last):

(x - 8)(x + 5) = x * x + x * 5 - 8 * x - 8 * 5 = x² + 5x - 8x - 40 = x² - 3x - 40

The simplified expression is x² - 3x - 40.

г) (x + 6)²

To simplify this expression, use the formula for squaring a binomial: (a + b)² = a² + 2ab + b²

In this case, a = x and b = 6:

(x + 6)² = x² + 2 * x * 6 + 6² = x² + 12x + 36

The simplified expression is x² + 12x + 36.