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secondary 3 | A Maths
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Carrie Tan
Carrie Tan

secondary 3 chevron_right A Maths

I need help in these two qns. Thanks

Date Posted: 7 years ago
Views: 613

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Clovis Nyu
Clovis Nyu's answer
9 answers (Tutor Details)
1st
Basically find the minimum point. That is the lowest point of the curve so if that is above y=-3, the whole graph will be above it. Its a minimum point and not a maximum as the coefficient of x^2 is positive.
Left is completing the square right is differentiation.
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Mong Chang Hsi
Mong Chang Hsi's answer
39 answers (Tutor Details)
Sorry for blur picture but just have to take two equations substitute together and equate to 0. using discriminant < 0 to find the range
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Mong Chang Hsi
Mong Chang Hsi's answer
39 answers (Tutor Details)
For part 2, use discriminant then complete the square and simple explanation about the square is always greater than 0
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Mong Chang Hsi
Mong Chang Hsi's answer
39 answers (Tutor Details)
Easier way to complete the square, you can google more on how to do it the quicker way