Tolong yang bisa, pakai cara ya..... Ngasal=report

Tolong yang bisa, pakai cara ya.....
Ngasal=report

Tolong yang bisa, pakai cara ya…..
Ngasal=report

Misal p = 1 / a + 2b dan q = 1/a-b maka

9p + q = 2 dan 9p -2q = -1 diperoleh p = 1/9 dan q = 1

a + 2b = 9 dan a – 2b = 1, diperoleh :

2a = 10 a = 5

a + 2b= 9 5x + 2b = 9 b= 2

a – b² = 5-4 = 1 (A)

Dimisalkan :

$frac{1}{a:+:2b}:=:x::::text{dan}::::frac{1}{a:-:2b}:=:y$

Maka :

$frac{9}{a:+:2b}:+:frac{1}{a:-:2b}:=:2:::to:::9x:+:y:=:2:::...:::(:i:)$

$frac{9}{a:+:2b}:-:frac{2}{a:-:2b}:=:-1:::to:::9x:-:2y:=:-1:::...:::(:ii:)$

( i ) – ( ii ) :

9x + y = 2

9x – 2y = -1

________ –

3y = 3

y = 1

Substitusikan nilai y ke ( i ) :

9x + y = 2

9x + 1 = 2

9x = 2 – 1

9x = 1

x = ¹/₉

$text{Karena}::x:=:frac{1}{a:+:2b},::text{maka}:::::a:+:2b:=:frac{1}{x}:=:frac{1}{frac{1}{9}}:=:9:::...::(:iii:)$

$text{Karena}::y:=:frac{1}{a:-:2b},::text{maka}:::::a:-:2b:=:frac{1}{y}:=:frac{1}{1}:=:1:::...::(:iv:)$

( iii ) + ( iv ) :

a + 2b = 9

a – 2b = 1

________ +

2a = 10

a = 5

Substitusikan nilai a ke ( iv ) :

a – 2b = 1

5 – 2b = 1

–2b = 1 – 5

–2b = –4

b = 2

Sehingga :

a – b² = 5 – 2²

a – b² = 5 – 4

a – b² = 1

Jawaban : ( A )