Plz help on rationalising surds

Mathematics

1 answer:

Fittoniya [83]2 years ago

3 0

(√5 + 3)² / √20=
((√5 + 3)² / √20)(√20/√20)=
(√20(√5 + 3)²) / (√20)²=
√20(5+6√5+9) /20=
√20 (14+6√5) /20=
(14√20 +6√100) /20=
(14√20 +60) / 20=
(14(√4√5) + 60) /20=
(14(2)(√5)+60) / 20=
(28√5+60) /20=
(7√5+15) / 5

Answer:(√5 + 3)² / √20= <span>(7√5+15) / 5</span>

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