In a geometric sequence, the first term, a1, is equal to 3 , and the fifth term, a5, is equal to 48 . Which number represents the common ratio of the geometric sequence?r=1r=2r=3r=4
Q. In a geometric sequence, the first term, a1, is equal to 3 , and the fifth term, a5, is equal to 48 . Which number represents the common ratio of the geometric sequence?r=1r=2r=3r=4
Identify Formula for nth Term: Identify the formula for the nth term of a geometric sequence. The nth term of a geometric sequence can be found using the formula an=a1×r(n−1), where an is the nth term, a1 is the first term, and r is the common ratio.
Set Up Equation: Set up the equation using the given terms.We know that a1=3 and a5=48. We can use the formula from Step 1 to write the equation for the fifth term: 48=3⋅r5−1.
Simplify Equation: Simplify the equation.48=3×r4Now, we need to solve for r.
Divide to Isolate r4: Divide both sides of the equation by 3 to isolate r4.348=r416=r4
Take Fourth Root to Solve: Take the fourth root of both sides to solve for r.r=161/4r=2
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