Answer
1 positive real zero.
2 or 0 negative real zeros.
Work Step by Step
Step 1. For $f(x)=-6x^5+x^4+5x^3+x+1$, we can find 1 sign change indicating that there will be 1 positive real zero.
Step 2. For $f(-x)=6x^5+x^4-5x^3-x+1$, we can find 2 sign changes indicating that there may be 2 or 0 negative real zeros.
