Question

(3x+2)(2x-1)-3x(2x+3)+2x при x=-0,4

Answer 1

6x^2-3x+4x-2-6x^2+9x+2x=-3x+4x-2-9x+2x=-6x-2=-6*(-0.4)-2=0.4

Answer 2

To evaluate the expression (3x+2)(2x-1) - 3x(2x+3) + 2x at x = -0.4, simply substitute the value of x into the expression and perform the calculations:

Let's start with the expression: (3x + 2)(2x - 1) - 3x(2x + 3) + 2x

Now, plug in x = -0.4: (3(-0.4) + 2)(2(-0.4) - 1) - 3(-0.4)(2(-0.4) + 3) + 2(-0.4)

Now, calculate each part of the expression step by step:

1. (3(-0.4) + 2) = (-1.2 + 2) = 0.8
2. (2(-0.4) - 1) = (-0.8 - 1) = -1.8
3. 3(-0.4) = -1.2
4. 2(-0.4) + 3 = (-0.8 + 3) = 2.2
5. 3(-0.4)(2(-0.4) + 3) = 3(-1.2)(2.2) = -7.92
6. 2(-0.4) = -0.8

Now, substitute the calculated values back into the original expression:

0.8 * -1.8 - (-1.2) * 2.2 + (-0.8)

Now, perform the arithmetic operations:

-1.44 - (-2.64) - 0.8 -1.44 + 2.64 - 0.8 1.2 - 0.8 = 0.4

Therefore, when x = -0.4, the value of the expression (3x+2)(2x-1) - 3x(2x+3) + 2x is 0.4.