First you have all ten books, but then every time after, you loose one because you can't put the same book in the group twice.
10 * 9 * 8 * 7 = 5040 groups
We have to find the GCD between 10, 16 and 4 and between x^5, x^4 and x^2
GCD (10,16,4) = 2
GCD (x^5,x^4,x^2) = x^2
So we divide all terms for 2x^2
Final result: 2x^2(5x^3-8x^2+2)
In mathematical analysis, Clairaut's equation is a differential equation of the form where f is continuously differentiable. It is a particular case of the Lagrange differential equation
6 pounds of meat
3 / 4 * 8 = 6