223
1). ...=
=
2)...=
=
3)...=
=
4)...=
=
224
1). 2a^3 + 9 - 2(a+1)(a^2 - a + 1) = 2a^3 + 9 - 2(a^3 + 1) = 2a^3 + 9 - 2a^3 - 2 = 7
2). x(x+2)(x-2) - (x-3)(x^2+3x+9) = x(x^2 - 4) - (x^3 - 27) = x^3 - 4x - x^3 + 27 = -4x + 27 при х = 1/4: -4*1/4 + 27 = -1 + 27 = 26
3). 3(b-1)^3 + (b+2)(b^2-2b+4) - (b+1)^3 = 3(b^3 - 3b^2 + 3b - 1) + b^3 + 8 - (b^3 + 3b^2 + 3b + 1) = 3b^3 - 9b^2 + 9b - 3 + b^3 + 8 - b^3 - 3b^2 - 3b - 1 = 3b^3 - 12b^2 + 6b + 4
при b = -1/3
-3/27 - 12/9 - 6/3 + 4 = - 1/9 - 12/9 - 18/9 + 4 = -31/9 + 4 = (36-31)/9 = 5/9
4). (a-1)^3 - 4a(a+1)(a-1) + 3(a-1)(a^2+a+1) = a^3 - 3a^2 + 3a - 1 - 4a(a^2 - 1) + 3(a^3 - 1) = a^3 - 3a^2 + 3a - 1 - 4a^3 + 4 + 3a^3 - 3 = - 3a^2 + 3a
при а = -2
-3 * 4 + 3 * (-2) = -12 -6 = -18
3m(-3,6;-1,5)
1/4n(2;-1,05)
q(-1,6;-2,55)
Sn=(b1*(1-q^n))/1-q
b1=36
b2=-18,9
q=b2/b1=-18,9/36
q=-0,525
n=8
S8=(36*(1-(-0,525)^8)/1-(-0,525)
S8=(36*0,994)/1,525=23,4703