( , , ) = ( , , ) = 2 2 2 (5 − 2 + ) ( + + − 30) = −2 = (2 ) 1 = − (2) ( , , ) = ( , , ) = 2 2 2 (5 − 2 + ) = ( + + − 30) 1 = (2 ) 1 = (3) 2 , ) = + + − 30 = 0 (4) ( , 2 2 2 Dari (1) dan (2) diperoleh = 1 2 5 1 = − 2 5 = −2 2 = − (5) 5 33