Question

(−a2−4ab)−(2a2−b2−ab) если a=2 и b=−2.

Answer 1

сначала нужно упростить:

-а²-4аb-2a²+b²+ab = -3a²-3ab+b²

если а=2, б=-2, то -3*2²-3*2*(-2)+(-2)² = -12+12+4 = 4

Answer 2

To evaluate the expression (-a^2 - 4ab) - (2a^2 - b^2 - ab) with the given values a=2 and b=-2, we simply substitute these values into the expression and perform the arithmetic operations. Let's do that step by step:

Step 1: Replace a with 2 and b with -2 in the expression. (-a^2 - 4ab) - (2a^2 - b^2 - ab)

(-2^2 - 4(2)(-2)) - (2(2)^2 - (-2)^2 - (2)(-2))

Step 2: Perform the arithmetic operations inside the parentheses. (-4 - 4(-2)) - (2(4) - 4 - (-4))

(-4 + 8) - (8 - 4 + 4)

Step 3: Continue simplifying the expression. 4 - 8

Step 4: Final result. -4

So, the value of the expression (-a^2 - 4ab) - (2a^2 - b^2 - ab) with a=2 and b=-2 is -4.