Question

-20ab-(5a+2b)². a=√4 b=√5

Answer 1

-20ab-(25a^2+20ab+4b^2)
-20ab-25a^2-20ab-4b^2
-25a^2-40ab-4b^2
-25*4-40*корень из 20-4*5=
-100-20-40*корень из 20
Ответ:-40√20-120

Answer 2

-20аb-(5a+2b)²=-20ab-25a²-20ab-4b²=
-40ab-25a²-4b²=-40√4*√5-25(√4)²-4(√5)²=
-80√5-100-20=-120-80√5=-40(3+2√5)

Answer 3

To evaluate the expression -20ab - (5a + 2b)² with the given values of a = √4 and b = √5, follow these steps:

Step 1: Substitute the values of a and b into the expression. Step 2: Perform the calculations as per the order of operations (PEMDAS/BODMAS).

Let's go ahead and perform the calculations:

Step 1: Substitute the values of a and b a = √4 = 2 b = √5 ≈ 2.236 (rounded to 3 decimal places)

Step 2: Perform the calculations -20ab - (5a + 2b)² = -20(2)(2.236) - (5(2) + 2(2.236))² = -40(2.236) - (10 + 4.472)² = -40(2.236) - (14.472)² = -40(2.236) - 209.110 ≈ -89.440

So, the value of the expression -20ab - (5a + 2b)² with a = √4 and b = √5 is approximately -89.440 (rounded to 3 decimal places).