find the value of a and b if
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7+3√5/ 3+√5 - 7-3√5/3-√5 = a+b√5
first rationalise each one
7+3√5/3+√5 × 3-√5/3-√5
= 7 + 3√5 ( 3-√5)/3²-5
= 21-7√5 +9√5 - 15 /4
=6 +2√5/4
= 2(3+√5)/4
=3+√5/2
7-3√5/3-√5 × 3+√5/3+√5
=7-3√5(3+√5)/4
=21+7√5-9√5-15/4
=3-√5/2
putting both together
3+√5/2 - 3-√5/2=a+b√5
first rationalise each one
7+3√5/3+√5 × 3-√5/3-√5
= 7 + 3√5 ( 3-√5)/3²-5
= 21-7√5 +9√5 - 15 /4
=6 +2√5/4
= 2(3+√5)/4
=3+√5/2
7-3√5/3-√5 × 3+√5/3+√5
=7-3√5(3+√5)/4
=21+7√5-9√5-15/4
=3-√5/2
putting both together
3+√5/2 - 3-√5/2=a+b√5
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