Tolong dijawab ya pls

√{(a+b) - 2√(a.b)} = √a - √b
√{(a+b) + 2√(a.b)} = √a + √b
seperti itu aturannya

dijabari satu2 ajah dulu
√(19 - 8√3) = √(19 - 2.4√3)
= √(19 - 2√(16.3))
= √{(16+3) - 2√(16.3)
= √16 - √3
= 4 - √3

√{12 + 6√3} = √{12 + 2.3√3}
= √{(9+3) + 2√(9.3)}
= √9 + √3
= 3 + √3

maka
= {4 - √3 - (3 + √3)} / (2√3 - 1)
= {4 - √3 - 3 - √3} / (2√3 - 1)
= (1 - 2√3) / (2√3 - 1)
= -1(2√3 - 1) / (2√3 - 1)
= -1