(2√27-√15) (6√3+√15)

(2akar27 - akar 15) (6akar 3 + akar 15)

=2akar 27 (6 akar 3 + akar 15) - akar 15 (6 akar 3 + akar 15)

= 12 akar (27×3) + 2 akar (27×15) - 6 akar (15×3) - akar (15×15)

= 12 akar 81 + 2 akar 405 - 6akar 45 - akar (15^2)

= (12 × 9) + 2 akar (81×5) - 6 akar (9×5) - 15

= (108 - 15) + (2akar 81 × akar 5) - (6 akar 9 × akar 5)

= 93 + (2 × 9 ×akar5) - (6 × 3 × akar 5)

= 93 + 18 akar 5 - 18 akar 5

= 93 + 0

= 93

semoga membantu

Huruf V = melambangkan akar
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(2V27 - V15) (6V3 + V15)
》12V81 + 2V405 - 6V45 - 15
》 12.9 + 2V81.5 - 6V9.5 - 15
》 108 + 2.9V5 - 6.3V5 -15
》 108 - 15 + 18V5 - 18V5
》 93