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

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

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

a

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

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

\(2 ⋅ {}^{3}\!\log(a + 5)\)

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

c

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

1p

○

\(\text{ } = {}^{3}\!\log(a^{2} + 10 a + 25)\)

1p

2p

d

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

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

d

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

1p

○

\(\text{ } = {}^{4}\!\log(x^{2} ⋅ (3 x - 1))\)
\(\text{ } = {}^{4}\!\log(3 x^{3} - x^{2})\)

1p

opgave 2

Herleid tot één logaritme.

2p

a

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

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

a

\(3 + {}^{5}\!\log(4 x - 2)\)
\(\text{ } = {}^{5}\!\log(5^{3}) + {}^{5}\!\log(4 x - 2)\)
\(\text{ } = {}^{5}\!\log(125) + {}^{5}\!\log(4 x - 2)\)

1p

○

\(\text{ } = {}^{5}\!\log(125 ⋅ (4 x - 2))\)
\(\text{ } = {}^{5}\!\log(500 x - 250)\)

1p

3p

b

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

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

b

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

1p

○

\(\text{ } = {}^{2}\!\log(2^{5}) + {}^{2}\!\log(x + 3)\)
\(\text{ } = {}^{2}\!\log(32) + {}^{2}\!\log(x + 3)\)

1p

○

\(\text{ } = {}^{2}\!\log(32 ⋅ (x + 3))\)
\(\text{ } = {}^{2}\!\log(32 x + 96)\)

1p

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