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secondary 2 | Maths
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Ken
Ken

secondary 2 chevron_right Maths chevron_right Singapore

how do I find the answer for part c? tysm

Date Posted: 3 years ago
Views: 176

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Zhe Xun
Zhe Xun's answer
113 answers (Tutor Details)
1st
Pls ignore right side if you havent learnt differentiation
Eric Nicholas K
Eric Nicholas K
3 years ago
For the Sec 2 level the “take average of x-intercepts” approach should suffice. Differentiation is probably a little too advanced for the student.
The curve is symmetrical. The minimum point lies on the line of symmetry.
Both x-intercepts (which are mirror images of each other) are equidistant from the line of symmetry. So the midpoint between them lies on this line as well.
x-coordinate of the midpoint = (3 + 7)/2 = 10/2 = 5
This tells you that the line of symmetry has equation x = 5. Which means that the minimum point has an x-coordinate of 5 .
When x = 5, y = (5 - 3)(5 - 7) = (2)(-2) = -4
So the minimum point has coordinates (5,-4)
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J
J's answer
1022 answers (A Helpful Person)
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Yu Meng Tan
Yu Meng Tan's answer
4 answers (Tutor Details)
find min or maximum point, dy/dx curve at let it = 0. hope it helps!
Eric Nicholas K
Eric Nicholas K
3 years ago
“dy/dx” might be slightly too advanced for a Secondary 2 student.