Getal & Ruimte (12e editie) - vwo wiskunde B

'Logaritmen herleiden'.

vwo wiskunde B 9.1 Rekenregels voor logaritmen

Logaritmen herleiden (6)

opgave 1

Herleid tot één logaritme.

1p

a

\({}^{5}\!\log(4 p) + {}^{5}\!\log(3 p - 1)\)

Optellen (1)
00ku - Logaritmen herleiden - basis - basis - 0ms - dynamic variables

a

\({}^{5}\!\log(4 p) + {}^{5}\!\log(3 p - 1)\)
\(\text{ } = {}^{5}\!\log(4 p ⋅ (3 p - 1))\)
\(\text{ } = {}^{5}\!\log(12 p^{2} - 4 p)\)

1p

1p

b

\({}^{2}\!\log(3 a) - {}^{2}\!\log(4 a + 5)\)

Aftrekken
00kv - Logaritmen herleiden - basis - eind - 1ms - dynamic variables

b

\({}^{2}\!\log(3 a) - {}^{2}\!\log(4 a + 5)\)
\(\text{ } = {}^{2}\!\log({3 a \over 4 a + 5})\)

1p

2p

c

\(3 ⋅ {}^{2}\!\log(4 x)\)

Vermenigvuldigen
00kw - Logaritmen herleiden - basis - midden - 0ms - dynamic variables

c

\(3 ⋅ {}^{2}\!\log(4 x)\)
\(\text{ } = {}^{2}\!\log((4 x)^{3})\)

1p

○

\(\text{ } = {}^{2}\!\log(64 x^{3})\)

1p

2p

d

\(3 ⋅ {}^{4}\!\log(a) + {}^{4}\!\log(2 a + 1)\)

OptellenVermenigvuldigen
00kx - Logaritmen herleiden - basis - eind - 0ms - dynamic variables

d

\(3 ⋅ {}^{4}\!\log(a) + {}^{4}\!\log(2 a + 1)\)
\(\text{ } = {}^{4}\!\log(a^{3}) + {}^{4}\!\log(2 a + 1)\)

1p

○

\(\text{ } = {}^{4}\!\log(a^{3} ⋅ (2 a + 1))\)
\(\text{ } = {}^{4}\!\log(2 a^{4} + a^{3})\)

1p

opgave 2

Herleid tot één logaritme.

2p

a

\(2 + {}^{5}\!\log(x - 4)\)

Grondtal (1)
00ky - Logaritmen herleiden - basis - midden - 0ms - dynamic variables

a

\(2 + {}^{5}\!\log(x - 4)\)
\(\text{ } = {}^{5}\!\log(5^{2}) + {}^{5}\!\log(x - 4)\)
\(\text{ } = {}^{5}\!\log(25) + {}^{5}\!\log(x - 4)\)

1p

○

\(\text{ } = {}^{5}\!\log(25 ⋅ (x - 4))\)
\(\text{ } = {}^{5}\!\log(25 x - 100)\)

1p

3p

b

\({}^{2}\!\log(8) + {}^{4}\!\log(5 x + 1)\)

Grondtal (2)
00kz - Logaritmen herleiden - basis - eind - 0ms - dynamic variables

b

\({}^{2}\!\log(8) + {}^{4}\!\log(5 x + 1)\)
\(\text{ } = {}^{2}\!\log(2^{3}) + {}^{4}\!\log(5 x + 1)\)
\(\text{ } = 3 + {}^{4}\!\log(5 x + 1)\)

1p

○

\(\text{ } = {}^{4}\!\log(4^{3}) + {}^{4}\!\log(5 x + 1)\)
\(\text{ } = {}^{4}\!\log(64) + {}^{4}\!\log(5 x + 1)\)

1p

○

\(\text{ } = {}^{4}\!\log(64 ⋅ (5 x + 1))\)
\(\text{ } = {}^{4}\!\log(320 x + 64)\)

1p

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