Question

Va rog ajutati-ma cu acest exercitiu la matematica

Answer 1

a/b=2√2-1
(a/b)²=(2√2-1)²
a²/b²=8-4√2+1=9-4√2

r=(a²+7b²)/(a²-b²)   impartim si numaratorul si numitorul cu b²
=(a²/b²+7b²/b²)/(a²/b²-b²/b²)=
=(a²/b²+7)/(a²/b²-1)=
inlocuim  a²/b²=9-4√2
=(9-4√2+7)/(9-4√2-1)=
=(16-4√2)/(8-4√2)=
=(4-√2)/(2-√2)=
=(4-√2)(2+√2)/(2-√2)(2+√2)=
=(8-2√2+4√2-2)/(4-2)=
=(6+2√2)/2=
=3+√2

Answer 2

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