Question

Simplify (5+2√3)(5-3√3)

Answer 1

25-18-15√3+10√3=7-5√3

Answer 2

$(5 + 2 \sqrt{ 3} )(5 - 3 \sqrt{3}) \\ = {5}^{2} + (5)( - 3 \sqrt{3} ) + (5)(2 \sqrt{3} ) + (2 \sqrt{3} )( - 3 \sqrt{3} ) \\ = 25 - 15 \sqrt{3} + 10 \sqrt{3} - 6 ({ \sqrt{3}) }^{2} \\ = 25 - 5 \sqrt{3} - 18 \\ = - 5 \sqrt{3} + 7 \\ = ( 7 - 5 \sqrt{3} )$