Arifmetik progressiya dastlabki n ta hadining yig'indisi — 9-sinf Algebra test savollari

1.a1 = 2, d = 3 bo'lgan arifmetik progressiyaning dastlabki 10 ta hadi yig'indisini toping.

• A)155
• B)150
• C)160
• D)140

2.a1 = 1, an = 19, n = 10 bo'lgan arifmetik progressiyaning yig'indisini toping.

• A)100
• B)190
• C)95
• D)105

3.a1 = 5, d = 2, n = 8 bo'lgan arifmetik progressiyaning yig'indisini toping.

• A)96
• B)88
• C)104
• D)80

4.1 + 2 + 3 + ... + 50 yig'indisini toping.

• A)1275
• B)1250
• C)1300
• D)1225

5.a1 = -3, d = 5, n = 12 bo'lgan arifmetik progressiyaning yig'indisini toping.

• A)294
• B)288
• C)300
• D)282

6.Arifmetik progressiya yig'indisining formulasini a1 va an orqali ko'rsating.

• A)Sn $=\frac{a1+an}{2}\cdot n$
• B)Sn = a1·n
• C)Sn $=\frac{a1-an}{2}\cdot n$
• D)Sn = a1 + an·n

7.a1 = 4, an = 24, n = 6 bo'lgan arifmetik progressiyaning yig'indisini toping.

• A)84
• B)90
• C)78
• D)96

8.2 + 4 + 6 + ... + 20 yig'indisini toping.

• A)110
• B)100
• C)120
• D)90

9.Arifmetik progressiyaning yig'indisi formulasini a1 va d orqali ko'rsating.

• A)Sn $=\frac{n}{2}\cdot \left(2a1+\left(n-1\right)d\right)$
• B)Sn = n · (a1 + d)
• C)Sn $=\frac{n}{2}\cdot \left(a1\cdot d\right)$
• D)Sn = n²·a1

10.a1 = 10, d = -2, n = 5 bo'lgan arifmetik progressiyaning yig'indisini toping.

• A)30
• B)20
• C)40
• D)25