Getal & Ruimte (13e editie) - vwo wiskunde B

'Logaritmen herleiden'.

vwo wiskunde B 9.2 Rekenregels voor logaritmen

Logaritmen herleiden (6)

opgave 1

Herleid tot één logaritme.

1p

a

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

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

a

\({}^{5}\!\log(2 x) + {}^{5}\!\log(3 x - 4)\)
\(\text{ } = {}^{5}\!\log(2 x ⋅ (3 x - 4))\)
\(\text{ } = {}^{5}\!\log(6 x^{2} - 8 x)\)

1p

1p

b

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

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

b

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

1p

2p

c

\(2 ⋅ {}^{4}\!\log(p + 5)\)

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

c

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

1p

○

\(\text{ } = {}^{4}\!\log(p^{2} + 10 p + 25)\)

1p

2p

d

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

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

d

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

1p

○

\(\text{ } = {}^{3}\!\log(x^{4} ⋅ (2 x - 5))\)
\(\text{ } = {}^{3}\!\log(2 x^{5} - 5 x^{4})\)

1p

opgave 2

Herleid tot één logaritme.

2p

a

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

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

a

\(3 + {}^{4}\!\log(2 a + 5)\)
\(\text{ } = {}^{4}\!\log(4^{3}) + {}^{4}\!\log(2 a + 5)\)
\(\text{ } = {}^{4}\!\log(64) + {}^{4}\!\log(2 a + 5)\)

1p

○

\(\text{ } = {}^{4}\!\log(64 ⋅ (2 a + 5))\)
\(\text{ } = {}^{4}\!\log(128 a + 320)\)

1p

3p

b

\({}^{4}\!\log(1\,024) + {}^{3}\!\log(2 x - 1)\)

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

b

\({}^{4}\!\log(1\,024) + {}^{3}\!\log(2 x - 1)\)
\(\text{ } = {}^{4}\!\log(4^{5}) + {}^{3}\!\log(2 x - 1)\)
\(\text{ } = 5 + {}^{3}\!\log(2 x - 1)\)

1p

○

\(\text{ } = {}^{3}\!\log(3^{5}) + {}^{3}\!\log(2 x - 1)\)
\(\text{ } = {}^{3}\!\log(243) + {}^{3}\!\log(2 x - 1)\)

1p

○

\(\text{ } = {}^{3}\!\log(243 ⋅ (2 x - 1))\)
\(\text{ } = {}^{3}\!\log(486 x - 243)\)

1p

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