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Prove that (3n+1)²-(3n-1)² is a multiple of 4 taking into account that n is a positive integer value

  1. Square the brackets (3n+1)²= (3n+1)(3n+1) = 9n²+3n+3n+1 = 9n²+6n+1 (3n-1)²= (3n-1)(3n-1) = 9n²-3n-3n+1 = 9n²-6n+12. Write out the full equation (9n²+6n+1) - (9n²-6n+1) = 9n²+6n+1-9n²+6n-1 = 12n3. Ex...
NK
Answered by Nalin K. Maths tutor
6885 Views

How do you solve two simultaneous equations? (i.e. 5x + y =21 and x - 3y =9)

There are two ways of solving the simultaneous equations. The easiest one is to write two equations beneath each other and then try to get either x or y values the same on both of them by multiplying the ...

PM
Answered by Paulina M. Maths tutor
3030 Views

Explain the process of how giraffes may have evolved to have long necks (6 marks)

There is natural variation in the lengths of giraffes' necks. As there will be competition for food with other giraffes and other species, those with longer necks would r...

KS
Answered by Kate S. Biology tutor
9306 Views

How does a vaccination protect an individual from illness and how is the spread of a pathogen reduced by immunising a large proportion of the population?

In a vaccination there are small quantities of a dead or inactive version of the pathogen.When you inject it into the individual's body ...

CD
Answered by Ciara D. Biology tutor
4086 Views

Cosa ti piace fare nel tuo tempo libero ?

Nel mio tempo libero mi dedico allo sport, in particolare mi piace nuotare. Vado in piscina 4 volte a settimana, e nuoto per due ore, dopodiché torno a casa a studiare.Nel fine settimana di solito esco co...

MS
2849 Views

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