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When discussing multiplication of directed numbers with his friend, Jeremy remarked
'If the number of minus signs in the question is odd I know
the answer is going to be negative and if the number of minus
signs is even I know the answer is going to be positive'.
Is Jeremy correct? Justify your answer with examples. (3 marks)
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`text(Examples: odd number of minus signs)`
`1.\ -1xx-1xx-1=1xx-1=-1`
`2.\ -1xx-1xx-1xx-1xx-1=1xx(-1xx-1xx-1)=1xx1xx-1=1xx-1=-1`
`text(Examples: even number of minus signs)`
`1.\ -1xx-1=1`
`2.\ -1xx-1xx-1xx-1=1xx(-1xx-1)=1xx1=1`
`:.\ text(An odd number of minus signs = negative answer)`
`text(and an even number of minus signs = positive answer.)`
`text(Examples: odd number of minus signs)`
`1.\ -1xx-1xx-1=1xx-1=-1`
`2.\ -1xx-1xx-1xx-1xx-1=1xx(-1xx-1xx-1)=1xx1xx-1=1xx-1=-1`
`text(Examples: odd number of minus signs)`
`1.\ -1xx-1=1`
`2.\ -1xx-1xx-1xx-1=1xx(-1xx-1)=1xx1=1`
`:.\ text(An odd number of minus signs = negative answer)`
`text(and an even number of minus signs = positive answer.)`