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Solve the equation 3a^2+4a+1=3 for all values of a. Give your answers to 3 significant figures.

First take the 3 over the other side to make the right hand side zero, turning it into a homogeneous equation: 3a 2 +4a-2=0. Since the expression on the left hand side cannot be factorised, we have to use qu...
NA
Answered by Nida A. • Maths tutor
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Explain how the trunk of an elephant evolved using Darwin's theory of natural selection, and then Lamarck's theory.

According to Darwin's theory, genetic variation within the population means that some elephants are born with longer noses. Longer noses are better suited to the environment, so longer-nosed elephants are mo...
KP
Answered by Katie P. • Biology tutor
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Give the characteristics of a homolgous series.

A homologous series is a group of compounds that share the same functionl group. Members of the same series have similar chemical properties and show a gradation in physical properties. Each member differs f...
JW
Answered by Jessica W. • Chemistry tutor
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Explain the process of natural selection.

Mutation, meiosis and sexual reproduction causes variation amoung members of the same species. Species tend to produce more offspring than the environment can support leading to competition for food or preda...
JW
Answered by Jessica W. • Biology tutor
3093 Views

Solve the following inequality: x^2 + x -12<0

Firstly we have to factorize the quadratic. We do this by finding two numbers that multiply to -12 and add to 1.Looking at the factors of 12 we can see that x 2 +x-12= (x-3)(x+4)because -3 x 4 = 12 and 4-3=1...
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Answered by Joy S. • Maths tutor
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