tolong dong pliss makasih

a) = {7(2-√8) + 11(2+√8)} / (2+√8)(2-√8)
= (14 - 7√8 + 22 + 11√8) / 4-8
= (36 + 4√8)/-4
= -9 - √8
= -9 - 2√2

b) 4/(√3+√2) + 5/(√3-√2) - 3/(√2-1)
kerjain yg depan 2 dulu
= {4(√3-√2)+5(√3+√2)}/(3-2) - 3/(√2-1)
= (4√3-4√2+5√3+5√2)/1 - 3/(√2-1)
= (9√3 + √2) - 3/(√2 - 1)
baru kerjain sama yg belakangnya
= {(9√3+√2)(√2-1) - 3}/(√2-1)
= (9√6-9√3+2-√2-3) / (√2-1)
= (9√6 - 9√3 - √2 - 1) / (√2-1) × (√2+1)/(√2+1)
= (9√12-9√6-2-√2+9√6-9√3-√2-1) / (2-1)
= 9√12 - 9√3 - 2√2 - 3
= 18√2 - 9√3 - 2√2 - 3
= 9√3 - 2√2 - 3