# Question about differentiation and tangents and quadratics and stuff... :)

Printable View

• September 21st 2010, 02:54 PM
jgv115
Question about differentiation and tangents and quadratics and stuff... :)
I've got a basic understand of differentiation and working the equation of the tangent on a point of a parabola etc

I don't know how to do this question though:

For the curve $y=ax^2+bx+c$, where a,b and c are constants, it is given that at the points (2,12) and (-1,0) the slope of the tangent is 7 and 1 respectively. Find a, b and c.

How do I go about starting this question??
• September 21st 2010, 02:58 PM
skeeter
Quote:

Originally Posted by jgv115
I've got a basic understand of differentiation and working the equation of the tangent on a point of a parabola etc

I don't know how to do this question though:

For the curve $y=ax^2+bx+c$, where a,b and c are constants, it is given that at the points (2,12) and (-1,0) the slope of the tangent is 7 and 1 respectively. Find a, b and c.

How do I go about starting this question??

you are given that y(2) = 12 , y(-1) = 0 , y'(2) = 7, and y'(-1) = 1

If y(x) = ax^2 + bx + c , then y'(x) = 2ax + b

set up some equations in terms of a, b, and c and solve.
All times are GMT -8. The time now is 10:44 AM.
{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 2, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "github"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "english_confidence": 0.9406148791313171, "perplexity_flag": "middle"}