Construct fields of each of the following orders

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Construct fields of each of the following orders: \textbf{(a)} 9 \textbf{(b)} 49 \textbf{(c)} 8 \textbf{(d)} 81 (you may exhibit these as \frac{F[x]}{(f(x))} for some F and f).

Relevant Theorems to use:
\textbf{(1.)} Let f(x) be a polynomial in F[x]. \frac{F[x]}{(f(x))} is a field iff f(x) is irreducible.

\textbf{(2.)} F is a finite field of order q and let f(x) be a polynomial in F[x] of degree n \geq 1. Then \frac{F[x]}{(f(x))} has q^n elements
 
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I think you should use the two theorems
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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