Question

Пeрший члeн арифмeтичноіі прогрeсіі -4 а різніця 2 знайтии суму пeрших дeсяти члeнів прогрeсіі

Answer 1

Решение:
Sn=(a1+an)*n/2
an=a1+d*(n-1)
Нам дано:
a1=-4
d=2
n=10
a10=-4+2*(10-1)=-4+2*9=-4+18=14
Отсюда:
S10=(-4+14)*10/2=10*5=50

Ответ: S10=50

Answer 2

Arithmetic Progression and Sum of First Ten Terms

To find the sum of the first ten terms of an arithmetic progression, we can use the formula:

Sum of first n terms = n/2 * (2a + (n-1)d)

Where: - n = number of terms - a = first term - d = common difference

Given that the first term (a) is -4 and the common difference (d) is 2, we can use these values to calculate the sum of the first ten terms.

Using the formula: Sum of first 10 terms = 10/2 * (2*(-4) + (10-1)*2)

Calculating: Sum of first 10 terms = 5 * (-8 + 18) = 5 * 10 = 50

Therefore, the sum of the first ten terms of the given arithmetic progression is 50.