In a geometric sequence, the first term, a1, is equal to 2 , and the third term, a3, is equal to 72 . Which number represents the common ratio of the geometric sequence?r=6r=7r=8r=9
Q. In a geometric sequence, the first term, a1, is equal to 2 , and the third term, a3, is equal to 72 . Which number represents the common ratio of the geometric sequence?r=6r=7r=8r=9
Identify Given Terms: Identify the given terms in the geometric sequence.We are given the first term a1 as 2 and the third term a3 as 72. In a geometric sequence, each term is found by multiplying the previous term by the common ratio r.
Write Formula for Third Term: Write the formula for the third term of a geometric sequence.The third term a3 can be expressed in terms of the first term a1 and the common ratio r as follows:a3=a1⋅r2
Substitute Known Values: Substitute the known values into the formula.We know that a1=2 and a3=72, so we can substitute these values into the formula:72=2×r2
Solve for Common Ratio: Solve for the common ratio r. To find r, we need to divide both sides of the equation by 2: 72/2=r236=r2 Now, take the square root of both sides to solve for r: 36=rr=6
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