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secondary 3 | A Maths
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I don't understand the solution for (ii) can someone explain it to me, thx.
Date Posted: 1 year ago
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Square of x where x is -3 is 9, which is positive (for all real value of x, x square is positive).
Since negative times positive equals negative, hence -2x² is negative.
Since negative times positive equals negative, hence -2x² is negative.
Add 4 on both side, since -2x²≤0, -2x²+4≤4
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