B1 = 49
b2 = 7
q = b2/b1 = 7/49 = 1/7
S = b1/(1 - q) = 49/(1 - 1/7) = 49/6/7 = 343/6
Январь - n
февраль - 1,1n
март - 1,2*1,1n = 1,32n
за три месяца = n + 1,1n + 1,32n = 3,42n
(sin20*sin80)*(sin40*sin60)=1/2(cos20-cos100)*1/2*(cos20-cos100)=
=1/4(cos20-cos100)²=1/4*(2sin60sin40)=1/4*4*3/4sin40=3/4*sin40
1. Вычислите:
а) (2-3i)+(i+1)=2-3i+i+1=-2i+3
б) (2-3i)+(-1-i)=2-3i-1-i=-4i+1
в) (2-3i)-(i+1)=2-3i-i-1=-4i+1
г) (i+1)-(-1-i)= i+1+1+i=2i+2
д) (2-3i)x(i+1)=2i+2-3i^2+3i=+3i^2-i+2
е) (-1-i)x(i+1)=-i-1-i^2-1=-i^2-i-2
2. Вычислите:
a) (2-i)(2+i)-(3-2i)+7=2^2+i^2-3+2i+7=4-i^2-3+2i+7=-i^2+2i+8
<span>б) (1+i)^4=((1+i)^2)^2=(1+2i+i^2)^2=1+4i+i^4</span>