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Show by induction that sum_n(r*3^(r-1))=1/4+(3^n/4)*(2n-1) for n>0

Base Case n=1sum_1(r3^(r-1))=13^0=1=1/4+(3^1/4)(2-1)=1/4+3/4=1
Assume true for n=ki.e. sum_k(r3^(r-1))=(3^k/4)(2k-1)
then for n=k+1sum_(k+1)(r3^(r-1))= sum_k(r3^(r...

Answered by • Maths tutor
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Compare and contrast the structure of DNA and RNA (3 marks)

Similarities: - Both consist of a pentose sugar, a phosphate group and 4 nitrogenous bases.- Both are joined by covalent phosphodiester bo...

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Answered by Anna A. • Biology tutor
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Why are there only 20 amino acids?

NB this question is discussion based and could be approached from many different angles and include more ideas than I have covered below. I have split this question into 2 parts. Firstly you could dress w...

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22177 Views

Describe how the lungs are adapted for gas exchange (6 marks)

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