Question

7 i and 2
Please help me

Answer 1

it's your7th1 answer

Answer 2

$( (\sqrt{4} + \sqrt{5} ) \div ( \sqrt{4} - \sqrt{5} )) + (( \sqrt{4} - \sqrt{5} ) \div ( \sqrt{4} + \sqrt{5} )) \\ \\ = ( (16 + 5 + 8 \sqrt{5} ) + (16 + 5 - 8 \sqrt{5} )) \div ( 16 - 5) \\ = 42 \div 11 \\ formulae \\ (x + y)^{2} = {x}^{2} + {y}^{2} + 2.x.y \\ {x}^{2} + {y}^{2} - 2.x.y = (x - y )^{2} \\ {x}^{2} - {y}^{2} = (x + y)(x - y)$