Haruka and Mustafa were asked to find an explicit formula for the sequence 4,12,36,108,…, where the first term should be g(1).Haruka said the formula is g(n)=4⋅3n, andMustafa said the formula is g(n)=4⋅4n−1.Which one of them is right?Choose 1 answer:(A) Only Haruka(B) Only Mustafa(C) Both Haruka and Mustafa(D) Neither Haruka nor Mustafa
Q. Haruka and Mustafa were asked to find an explicit formula for the sequence 4,12,36,108,…, where the first term should be g(1).Haruka said the formula is g(n)=4⋅3n, andMustafa said the formula is g(n)=4⋅4n−1.Which one of them is right?Choose 1 answer:(A) Only Haruka(B) Only Mustafa(C) Both Haruka and Mustafa(D) Neither Haruka nor Mustafa
Identifying the Pattern: We have the sequence: 4,12,36,108,…To determine which formula is correct, we need to identify the pattern of the sequence.
Checking Haruka's Formula: The sequence appears to be geometric because each term is multiplied by the same factor to get the next term.To find this common ratio r, we divide the second term by the first term: r=412=3.
Checking Mustafa's Formula: Now, let's check Haruka's formula: g(n)=4⋅3n.For n=1, g(1)=4⋅31=4⋅3=12, which does not match the first term of the sequence.Therefore, Haruka's formula is incorrect.
Checking Mustafa's Formula: Now, let's check Haruka's formula: g(n)=4⋅3n. For n=1, g(1)=4⋅31=4⋅3=12, which does not match the first term of the sequence. Therefore, Haruka's formula is incorrect.Let's check Mustafa's formula: g(n)=4⋅4(n−1). For n=1, g(1)=4⋅4(1−1)=4⋅40=4⋅1=4, which matches the first term of the sequence. For n=2, g(2)=4⋅4(2−1)=4⋅41=4⋅4=16, which does not match the second term of the sequence. Therefore, Mustafa's formula is also incorrect.
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