Q. Find the 8th term of the geometric sequence shown below.7x4,28x6,112x8,…Answer:
Identify common ratio: Identify the common ratio (r) of the geometric sequence by dividing the second term by the first term.Calculation: r=7x428x6
Calculate common ratio: Simplify the expression to find the common ratio.Calculation: r=4x2
Use nth term formula: Use the formula for the nth term of a geometric sequence, which is an=a1⋅r(n−1), where a1 is the first term and n is the term number.Calculation: The 8th term a8=7x4⋅(4x2)(8−1)
Simplify exponent: Simplify the exponent in the expression.Calculation: a8=7x4⋅(4x2)7
Raise common ratio: Raise the common ratio to the 7th power.Calculation: (4x2)7=47⋅(x2)7
Calculate values: Calculate the value of 47 and (x2)7.Calculation: 47=16384 and (x2)7=x14
Multiply first term: Multiply the first term 7x4 by the calculated values of 47 and x14.Calculation: a8=7x4⋅16384⋅x14
Combine like terms: Combine the like terms to find the 8th term.Calculation: a8=7⋅16384⋅x(4+14)
Multiply constants: Multiply the constants and add the exponents of x.Calculation: a8=114688⋅x18
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