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Find the 15th term or the geometric sequence 7, -21, 63,

User Cla
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1 Answer

7 votes

Answer:

33480783

Explanation:

Finding the Common Ratio:

We know that the formula for the common ratio of a GP is:

r = aₙ / (aₙ₋₁) (Where n is any integer)

replacing the values, taking n=2

r = -21 / 7

r = -3

Solving for the 15th Term:

We know that the Formula for the nth term of a GP:

G(n) = a * r ⁿ⁻¹ (where a is the first term and r is the common ratio)

replacing the values (taking n = 15 since we need the 15th term)

G(15) = 7 * (-3)¹⁴

G(15) = 33480783

Hence, the 15th term of the given GP is 33480783

User Hauleth
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