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If $$a^{2}+b^{2}$$+$$\frac{1}{a^{2}}$$+$$\frac{1}{b^{2}}$$=4 then the value of $$a^{2}+b^{2}$$ will be
$$a^2+b^2+\ \frac{\ 1}{a^2}+\ \frac{\ 1}{b^2}=4$$
$$a^2+b^2+\ \frac{\ 1}{a^2}+\ \frac{\ 1}{b^2}-4=0$$
$$a^2-2+\frac{\ 1}{a^2}+b^2-2+\ \frac{\ 1}{b^2}=0$$
$$\left(a-\ \frac{\ 1}{a}\right)^2+\left(b-\ \frac{\ 1}{b}\right)^2=0$$
Sum of squares is zero so both the terms are zero
$$=$$> $$\left(a-\ \frac{\ 1}{a}\right)^2=0$$, $$\left(b-\ \frac{\ 1}{b}\right)^2=0$$
$$=$$> $$a-\ \frac{\ 1}{a}=0$$, $$b-\ \frac{\ 1}{b}=0$$
$$=$$> $$a=\frac{\ 1}{a}$$, $$b=\frac{\ 1}{b}$$
$$=$$> $$a^2=1$$, $$b^2=1$$
Therefore $$a^2+b^2=1+1$$ = 2
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