19 uždavinys

18 uždavinys20 uždavinys

Sprendimas:

$log_{5}(x-7)$ = 0

$log_{5}(x-7)$ = $log_{5}(5^{0})$

$log_{5}(x-7)$ = $log_{5}(1)$

$x-7$ = $1$

$x$ = $8$

x = 8 patenka į apibrėžimo sritį.

Atsakymas: x = 8

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Sprendimas:

$sin(x)+sin(2\cdot x)$ = 0

$sin(x)+2\cdot sin(x)\cdot cos(x)$ = 0

$sin(x)\cdot (1+2\cdot cos(x))$ = 0

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$sin(x)$ = 0

$x$ = $\pi\cdot k$

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$1+2\cdot cos(x)$ = 0

$2\cdot cos(x)$ = $-1$

$cos(x)$ = $-\frac{1}{2}$

$x$ = $\frac{2\cdot \pi}{3}+2\cdot \pi\cdot k$

$x$ = $-\frac{2\cdot \pi}{3}+2\cdot \pi\cdot k$

Atsakymas: $x$ = $\pi\cdot k$ ir $x$ = $\frac{2\cdot \pi}{3}+2\cdot \pi\cdot k$ bei $x$ = $-\frac{2\cdot \pi}{3}+2\cdot \pi\cdot k$

18 uždavinys20 uždavinys