A1+2d+a1+3d=2a1+5d=5/12
S6=(2a1+5d)*6/2=5/12*3=5/4
Ну тип так
2x^2=8
x^2=4
x=2;-2
18_03_09_Задание № 1:
Вычислите (2−1)(2+1)(2^2+1)(2^4+1)(2^8+1)−2^16
РЕШЕНИЕ: (2−1)(2+1)(2^2+1)(2^4+1)(2^8+1)−2^16=(2^2−1^2)(2^2+1)(2^4+1)(2^8+1)−2^16=(2^2−1)(2^2+1)(2^4+1)(2^8+1)−2^16=(2^4−1^2)(2^4+1)(2^8+1)−2^16=(2^4−1)(2^4+1)(2^8+1)−2^16=(2^8−1^2)(2^8+1)−2^16=(2^8−1)(2^8+1)−2^16=2^16−1^2−2^16=-1
ОТВЕТ: -1