Question

1. 2x - y / xy при x = 0,4, y = -5 = ?2. 2a / a-b + 2a / a+b = ?

Answer 1

Пошаговое объяснение:

1. 2*0.4-(-5)/0.4*(-5)=-61.7

2. 2a / a-b + 2a / a+b = 4x^2/(x^2-y^2)

Answer 2

To evaluate the expressions, let's substitute the given values of x and y into the expressions and perform the calculations:

1. For the expression 2x - y / xy, with x = 0.4 and y = -5: 2(0.4) - (-5) / (0.4)(-5) = 0.8 + 5 / (-2) = 5.8 / (-2) = -2.9

Therefore, when x = 0.4 and y = -5, the value of 2x - y / xy is -2.9.

2. For the expression 2a / (a - b) + 2a / (a + b), there seems to be some ambiguity. Without knowing the specific values of a and b, we cannot provide a numerical result. However, we can simplify the expression:

2a / (a - b) + 2a / (a + b)

To combine these terms, we need a common denominator, which is (a - b)(a + b):

[2a(a + b) + 2a(a - b)] / [(a - b)(a + b)]

Simplifying further:

[2a^2 + 2ab + 2a^2 - 2ab] / [(a - b)(a + b)] = (4a^2) / [(a - b)(a + b)] = 4a^2 / (a^2 - b^2)

So, the simplified expression is 4a^2 / (a^2 - b^2). But to evaluate it numerically, we need specific values for a and b.