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Given,
$$x^4-4x+1=0$$
Let
$$f(x)=x^4-4x+1$$
Now,
$$f'(x)=4x^3-4=4(x^3-1)$$
Critical point is
$$x=1$$
Also,
$$f''(x)=12x^2>0$$
Hence, $$x=1$$ gives a minimum value.
Now,
$$f(1)=1-4+1=-2<0$$
Also,
$$\lim_{x\to\pm\infty}f(x)=+\infty$$
Further,
$$f(0)=1>0,\qquad f(2)=16-8+1=9>0$$
So, one root lies in $$(0,1)$$ and another root lies in $$(1,2)$$.
Also,
$$f(-1)=1+4+1=6>0$$
and the function is decreasing for $$x<1$$.
Hence, there is no negative root.
Therefore, the equation has exactly $$\boxed{2}$$ distinct real roots.
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