Jika a=2 dan b=3, tentukan nilai dari : b. (a−b)−3.(b−aa+b)−2.(a+b)−31

Pertanyaan

Jika $a = 2$ dan $b = 3$ , tentukan nilai dari :

b. $(a - b)^{- 3} . (\frac{a + b}{b - a})^{- 2} . \frac{1}{( a + b ) ^{- 3}}$

Pembahasan Soal:

Ingat!

Sifat bilangan berangkat:

$a^{- n} = \frac{1}{a ^{n}}$

Sehingga:

$= = = = = = = (a - b)^{- 3} . (\frac{a + b}{b - a})^{- 2} . \frac{1}{( a + b ) ^{- 3}} (2 - 3)^{- 3} . (\frac{2 + 3}{3 - 2})^{- 2} . \frac{1}{( 2 + 3 ) ^{- 3}} (- 1)^{- 3} . (\frac{5}{1})^{- 2} . \frac{1}{5 ^{- 3}} \frac{1}{( - 1 ) ^{3}} . \frac{1}{5 ^{2}} . \frac{1}{\frac{1}{5 ^{3}}} \frac{1}{( - 1 ) ^{3}} . \frac{1}{5 ^{2}} . \frac{5 ^{3}}{1} \frac{1}{- 1} . \frac{1}{25} . \frac{125}{1} - 1. \frac{1}{25} .125 - 5$

Dengan demikian, nilai dari $(a - b)^{- 3} . (\frac{a + b}{b - a})^{- 2} . \frac{1}{( a + b ) ^{- 3}}$ adalah $- 5$ .

Pembahasan terverifikasi oleh Roboguru

Dijawab oleh:

I. Sutiawan

Mahasiswa/Alumni Universitas Pasundan

Terakhir diupdate 30 Agustus 2021

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Ingat kembali:

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