Question

Question #e5721

Answer 1

Hello,

I suppose (x+1)C(3) means `\text{C}_{x+1}^3`. So, your equation becomes

`\frac{(x+1)x(x-1)}{6} = \frac{x(x-1)}{2}`

Obvious solutions are `x=0` and `x=1`.

If `x\ne 0` and `x\ne 1`, you can divide by `x(x-1)` because it's not zero, and you get

`\frac{x+1}{6} = \frac{1}{2}` therefore `x+1=3`, and the last solution is `x=2`.

Conclusion. The solutions are 0, 1 and 2.