4sin^2x-15cos^2x=4sinxcosx. Created by Kubns. matematika-ru

4sin^2x-15cos^2x=4sinxcosx...

Kubns @Kubns

July 2022 1 11 Report

4sin^2x-15cos^2x=4sinxcosx

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Удачник66

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$4sin^2(x)-4sin(x)*cos(x)-15cos^2(x)=0$
Делим всё на cos^2(x)
$4tg^2(x)-4tg(x)-15=0$
Получаем квадратное уравнение относительно tg(x)
D = 4^2 - 4*4(-15) = 16 + 16*15 = 256 = 16^2
tg x = (4 - 16)/8 = -12/8 = -3/2
x1 = -arctg(3/2) + pi*k
tg x = (4 + 16)/8 = 20/8 = 5/2
x2 = arctg(5/2) + pi*n

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17 kak reshit96a8b2013b2c94d76c0588d6f5f43ae0 78769

tgx24ctgx2 reshite uravnenie zaranee spasibo

SinXcosY=0,75 CtgXctgY=3...

6sin2x sinx 10

nomer 30 zaranee spasibo

kub rebro ravno 10 najti km

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Verified answer

17 kak reshit96a8b2013b2c94d76c0588d6f5f43ae0 78769

tgx24ctgx2 reshite uravnenie zaranee spasibo

SinX*cosY=0,75 CtgX*ctgY=3...

6sin2x sinx 10

nomer 30 zaranee spasibo

kub rebro ravno 10 najti km

рекомендуемые вопросы

Helpful Links

Helpful Social

SinXcosY=0,75 CtgXctgY=3...