Question

please can qnyone answer this question

Answer 1

x = 7 + √40  x = 7 + 2√10  = (√5)^2 + (√2)^2 + 2√(5*2)  = (√5 + √2)^2  √x = √5+√2  1/√x = 1/(√5+√2)  1/√x = (√5 - √2) / 3  √x + 1/√x = (3√5 + 3√2 + √5 - √2) / 3  √x + 1/√x = (4√5 + 2√2) / 3