multiplied by √2/√2

40[(√6-2)/(2√2)] * √2/√2

= (40(√6-2)√2) / (2√2)√2

= (40√12 - 80√2) / (2*2)

= 40(√12 - 2√2) / 4

= 10(√ (4*3) - 2√2)

= 10(2√3 - 2√2)

= 20(√3 - √2)

multiply by √2/√2

so, 40[(√6-2)/(2√2)]*√2/√2

then you have 40[((√6-2)*√2)/(2√2*√2)]

40[((√6-2)*√2)/(2*2)]

40[((√12-2√2)/4]

10(√12-2√2)

10(2√3-2√2)

10*2(√3-√2)

20(√3-√2)

hope this helps