Question

Manoj and shira asked to find an explicit formula for the sequence -9, -27, -81, -243....

Answer 1

Answer:

The answer is (B) ⇒ Only shira

Step-by-step explanation:

∵ the sequence is ⇒ -9 , -27 , -81 , -243 , .......

∵ -27 ÷ -9 = 3

∵ -81 ÷ -27 = 3

∴ The constant ratio is 3

∵ the first term is -9

∴ h(n) = -9(3)^n-1

∵ -9 = -3 × 3

∴ h(n) = -3 (3 × 3^n-1) ⇒ same base add the power

∴ $h(n)=-3(3^{n-1+1})=-3(3^{n})$

∴ Shira is right