Решение № 3 на фотографии.............
Решение смотри на фотографии
можу тільки другу сторону знайти Объяснение:SΔ=
ab×sinα
b=
2(x^2+х-12)/(2(3-х))^2
2(x^2+4х-3х-12)/2^2(3-х)^2
х(х+4)-3(х+4)/2(-(х-3))^2
(х+4)(х-3)/2(х-3)^2
х+4/2(х-3)
х+4/2х-6
<span> х^2-х-5=0
</span>1x2<span> - </span>1<span>x - </span>5<span> = </span>0
D<span> = b</span>2<span> - 4ac = (-1)</span>2<span> - 4∙1∙(-5) = 21</span>
D<span> > 0 ⇒ уравнение имеет 2 корня</span>
x<span> = -b ± √D / 2a</span>
<span>x1</span><span> = (1 - √21) / (2∙1) = -1.79128784748</span>
<span>x2</span><span> = (1 + √21) / (2∙1) = 2.79128784748
</span>
(1 - √21)³/8+(1+√21)³/8=(1-3√21+3√21²-√21³+1+3√21+3√21²+√21³)/8=(2+3*21+3*21)/8=128/8=<u>16</u>
