Tolong yg bisa kerjain

a) Lim x/(√(x + 4) - 2) . (√(x + 4) + 2)/(√(x + 4) + 2)
= Lim x(√(x + 4) + 2) / (x + 4 - 4)
= Lim (√(x + 4) + 2)
= √(0 + 4) + 2
= 2 + 2
= 4

b) Lim (x^2 - 9)/(√(x + 6) - 3) . (√(x + 6) + 3)/(√(x + 6) + 3)
= Lim (x^2 - 9)(√(x + 6) + 3) / (x + 6 - 9)
= Lim (x + 3)(x - 3)(√(x + 6) + 3) / (x - 3)
= Lim (x + 3)(√(x + 6) + 3)
= (3 + 3)(√(3 + 6) + 3)
= (6) (√9 + 3)
= 36

c) Lim x/(√(x + 9) - √(9 - x)) . (√(x + 9) + √(9 - x))/(√(x + 9) + √(9 - x))
= Lim x(√(x + 9) + √(9 - x)) / ((x + 9) - (9 - x))
= Lim x(√(x + 9) + √(9 - x)) / 2x
= Lim (√(x + 9) + √(9 - x)) / 2
= (√(0 + 9) + √(0 + 9)) / 2
= 6/2
= 3