Soal & Kunci Jawaban Matematika Kelas 9 SMP Halaman 58 59 Nomor 1 2 3 4 5 6 7 8 9 10 11 12 13

b. 7,27 × 10⊃2; – 0,5 × 10⊃3;
= (7,27 × 100) – (0,5 × 1000)
= 727 – 500
= 227
= 2,27 × 10⊃2;

c. (8,32 × 10⁴) : (4 × 10⁻⁶)
= (8,32 : 4) × 10⁴⁻⁽⁻⁶⁾
= 2,08 × 10⊃1;⁰

d. 3,7 × 10⊃3; × 5,2 × 10⁻⊃3;
= 3,7 × 5,2 × 10⊃3;⁺⁽⁻⊃3;⁾
= 19,24 × 10⁰
= 1,924 × 10

Soal nomor 7

a. x × y
= 24 × 54
= (2⊃3; × 3) × (2 × 3⊃3;)
= 2⊃3;⁺⊃1; × 3⊃3;⁺⊃1;
= 2⁴ × 3⁴
= (2 × 3)⁴
= 6⁴

b. x / y
= 24/54
= (2⊃3; x 3) / (2 x 3⊃3;)
= 2⊃3;⁻⊃1; × 3⊃1;⁻⊃3;
= 2⊃2; × 3⁻⊃2;
= 2⊃2; × 1/3⊃2;
= 2⊃2; / 3⊃2;
= (2/3)⊃2;

Soal nomor 8

492⁵ – 246⁵ =
= (246 × 2)⁵ – (246 × 1)⁵
= (2⁵ – 1⁵) × 246⁵
= (32 – 1) × 246⁵
= 31 × 246⁵

Soal nomor 9

1 tahun = 365 hari × 24 jam × 3600 detik = 31.536.000 detik
= 60.000 × 31.536.000 detik
= 1.892.160.000.000 detik

Jadi notasi ilmiah dari 60.000 tahun ke detik adalah 1,89216 × 10⊃1;⊃2; detik.

Soal nomor 10

a. -8 × 2⁶
= -1 × 8 × 2⁶
= -1 × 2⊃3; × 2⁶
= -1 × 2⊃3;⁺⁶
= -1 × 2⁹
= -2⁹
= -512

b. 5⁴ × 50
= 5⁴ × 25 × 2
= 5⁴ × 5⊃2; × 2
= 5⁴⁺⊃2; × 2
= 5⁶ × 2
= 15.625 × 2
= 31.250

c. 16/2⁴
= 2⁴/2⁴
= 2⁴⁻⁴
= 2⁰
= 1