Kelsey Ong Hui Ping's answer to Shion's Secondary 4 A Maths question.

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Kelsey Ong Hui Ping
Kelsey Ong Hui Ping's answer
22 answers (Tutor Details)
if the normal at x=-4 is perpendicular to the tangent, it means the tangent at x=-4 is parallel to the tangent. so dy/dx is still 15. hope this helps!