20 uždavinys

Sprendimas:

$5\cdot sin(30)-cos(2\cdot 30)+1$ = $5\cdot sin(30)-cos(60)+1$ = $\frac{5\cdot 1}{2}-\frac{1}{2}+1$ = $\frac{5}{2}+\frac{1}{2}$ = $3$

Atsakymas: 3

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Sprendimas:

f(x) = $5\cdot sin(x)-cos(2\cdot x)+1$

$cos(2\cdot x)$ = $cos(x)^{2}-sin(x)^{2}$

$5\cdot sin(x)-cos(2\cdot x)+1$ =

$5\cdot sin(x)-(cos(x)^{2}-sin(x)^{2})+1$ =

$5\cdot sin(x)-cos(x)^{2}+sin(x)^{2}+1$ =

$5\cdot sin(x)+sin(x)^{2}+1-cos(x)^{2}$ =

$5\cdot sin(x)+sin(x)^{2}+sin(x)^{2}$ =

$5\cdot sin(x)+2\cdot sin(x)^{2}$ =

$2\cdot sin(x)\cdot (2.5+sin(x))$

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Sprendimas:

$sin(x)$ = 0

$x$ = $\pi\cdot k$

kai k =	-2	-1	0	1	2
x =	-360, netinka	-180	0	180	360, netinka

$sin(x)+2.5$ = 0

$sin(x)$ = $-2.5$ , šaknų nėra

Atsakymas: -180°; 0°; 180°

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Sprendimas:

f(-x) = $2\cdot sin(-x)\cdot (2.5+sin((-x)))$ = $-2\cdot sin(x)\cdot (2.5-sin(x))$

negavome nei f(x), nei -f(x)

Atsakymas: nei lyginė, nei nelyginė

19 uždavinys21 uždavinys