(7x^3/2) - (4x^3/2)
Help please
If it were 7x - 4x, you'd have 3x. Similarly, 7x3/2 - 4x3/2 = 3x3/2.
May be math.not.maths's interpretation is correct, but I have another:
\(\dfrac{7x^3}{2}-\dfrac{4x^3}{2}\\ =\dfrac{3x^3}{2}\)
+30 
