Try this instead:

Also, squaring the first equation would get an expression involving every power of x between -2 and 4, which means that after cancelling with the second one you'd have a quintic thingy.]]>

Therefore,

1/a + 1 + a + a²=13.

1/a²+1+a²+a^4=1261.

Square the first equation, eleminate a^4.

Thereafter, you are left with a quadratic equation which, I guess, can be solved easily.]]>

(note, this had me stumped for ages, have fun )

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