Answer:
6
Step-by-step explanation:
Sum of first 4 numbers= 4*5= 20
This includes 3 + 4th number
Sum of last 4 numbers= 4*8= 32
This includes 4th number + 3
Sum of 7 numbers= 7*(6+4/7)= 46
This includes 3+4th number +3
Number common to both sets= (20+32)- 46 = 6
Answer:
In a quadratic equation of the shape:
y = a*x^2 + b*x + c
we hate that the discriminant is equal to:
D = b^2 - 4*a*c
This thing appears in the Bhaskara's formula for the roots of the quadratic equation:

You can see that the determinant is inside a square root, this means that if D is smaller than zero we will have imaginary roots (the graph never touches the x-axis)
If D = 0, the square root term dissapear, and this implies that both roots of the equation are the same, this means that the graph touches the x axis in only one point, wich coincides with the minimum/maximum of the graph)
If D > 0 we have two different roots, so the graph touches the x-axis in two different points.
Cube root (27a^12)
Cube root 27 = 3 because
3 * 3 * 3 = 27
Cube root a^12 = a^4 because
a^4 * a^4 * a^4 = a^12
ANSWER
3a^4

Write

, and recall that for a differentiable function

, the derivative at a point

is given by

which would suggest that for this limit,

and

. We have

, and so the value of the limit would be

.