1)(7-х)²=0 2)7-х²=0
7²-2*7*х+х²=0 7=х²
49-14х+х²=0 х1=√7≈2,64575 х2=-2,64575
х²-14х+49=0 Ответ: +-2,64575 Д=(-14)²-4*1*49=196-196=0
х1=х2=14/2*1=7
Ответ:7
5а^2-3(а+1)(а-1)+8а2+5=10а^2+8
5а^2-3(а^2-1)+8а^2+5=10а^2
5а^2-3а^2+3+8а^2+5=10а^2+8
10а^2+8=10а^2+8
Решение
1.
b) ∫cos⁵xsinxdx = - ∫cos⁵x d(cosx) = - (cos⁶x) / 6 + C
2.
b) ∫ctg3xdx = ∫[cos(3x)/sin(3x)] * d(x) = (1/3)*∫d(sin(3x)) / sin(3x) =
= (1/3)*lnIsin(3x)I + C
3. ∫sinxdx = - cosx
x = π; x = - π
- [cos(-π) - cosπ] = -[-1 - (-1)] = 0
4. ∫dx/3x = (1/3)*∫dx/x = (1/3)*lnIxI
x = e; x = 1
(1/3)*lne - (1/3)*ln1 = 1/3*1 - (1/3)*0 = 1/3
Объём конуса равен V = (1/3)So*H = (1/3)*12*3 = 12 м³.
<span><span>1)4a^3b-6a^2b^2= 2a^2b(2</span>а-3b)</span><span>2)5x^2y+10xy^2<span> =</span>5x<span>у(х+2у)
3)14</span>m^3-21m^2n^3=7m^2n(2m-3n<span>)
4)5</span>x^3-15x^2y+20xy^2=5x(x^2-3хy<span>+4у^2)
5)2</span>a^2y-6ay^2+8y=2у(a^2<span>-3ау+4)
6)6</span>ax-9a^2+15ax^2=3а(2х-3а+5x^2<span>)</span></span>