Question

16a^2-b^2/9ab:4a+b/a^2b при a=-0,3 b=-3

Answer 1

16a²-b²/9ab:4a+b/a²b       при  a=-0,3 b=-3

(16a²-b²)/9ab * a²b/(4a+b)=

=(4a-b)(4a+b)/9ab  *a²b/(4a+b)=

=(4a-b)/9   подставляем    a=-0,3    b=-3

(4a-b)/9=   [ (4*(-0,3) –(-3)]  /   9=

=(-1,2 +3)= 1,8        

Odp. : 1,8

Answer 2

To evaluate the given expression with the provided values of a and b, let's substitute a = -0.3 and b = -3 into the expression:

(16a^2 - b^2)/(9ab) : (4a + b)/(a^2b)

First, let's calculate the numerator and denominator separately:

Numerator: 16a^2 - b^2 = 16(-0.3)^2 - (-3)^2 = 16(0.09) - 9 = 1.44 - 9 = -7.56

Denominator: 9ab = 9(-0.3)(-3) = 0.27 * 3 = 0.81

Now, let's evaluate the second part of the expression:

(4a + b)/(a^2b) = (4(-0.3) + (-3))/((-0.3)^2(-3)) = (-1.2 - 3)/(0.09 * -3) = (-4.2)/(-0.27) = 15.5555555556

Finally, let's substitute the calculated values into the first part of the expression:

(-7.56)/(0.81) : 15.5555555556

To divide by a fraction, we can multiply by its reciprocal:

(-7.56)/(0.81) * (1/15.5555555556) = -7.56 * (1/15.5555555556) / 0.81 = -0.48641048641 / 0.81 = -0.6

Therefore, when a = -0.3 and b = -3, the value of the expression (16a^2 - b^2)/(9ab) : (4a + b)/(a^2b) is approximately -0.6.