Sin2x/since. ..................
X³ - 4x² - 11x = 0
x( x² - 4x - 11) = 0
x = 0
x² - 4x - 11 = 0
D = b² - 4ac = 16 - 4×(-11)= 16 + 44 = 60
x1 = ( 4 + 2√15) / 2 = 2( 2 + √15) /2 = 2 + √15
x2 = 2 - √ 15
Ответ: x1 = 2 + √15, x2 = 2 - √15, x3 = 0.
Bn=b1*q^(n-1)
q=b2/b1
Sn6=b1(q^6-1)/(q-1)
100 - 4= 96%.
96% - 1344 руб.
100% - х руб.
1344 × 100
----------------- =1400.
96
Ответ: 1400 руб.