help@askiitians.com

1800-150-456-789

Differential Calculus> tangents and normals at what points will ...

question mark

tangents and normals
at what points will the tangents to the curve y = 2x^3 – 15x^2 + 36x – 21 be parallel to x axis? also find the equations of the tangents to the curve at these points

taniska , 10 Years ago

Grade 12

1 Answers

Jitender Singh

Last Activity: 10 Years ago

Ans:
Hello Student,
Please find answer to your question below

$y = 2x^3 - 15x^2 + 36x - 21$
Slope of tangent: y’ = 0
$y' = 2.3x^2 - 15.2x + 36 = 0$
$6x^2 - 30x + 36 = 0$
$x^2 - 5x + 6 = 0$
$(x-3)(x-2) = 0$
$\Rightarrow x = 2, 3$
Find the corresponding y and thats gonna be the eauation of tangents.
x = 2
$y = 2.2^3 - 15.2^2 + 36.2 - 21$
$y = 16 - 60 + 72 - 21 = 7$
x = 3
$y = 2.3^3 - 15.3^2 + 36.3 - 21$
$y = 54 - 135 + 108 - 21 = 6$
y = 6 and y = 7 are equation of tangents.

Provide a better Answer & Earn Cool Goodies

LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

Full Live Access

Study Material

Live Doubts Solving

Daily Class Assignments

Ask a Doubt

Get your questions answered by the expert for free

the diameter of a roller is 84 cm and its length is 120 cm. it takes 500 complete revolution to move once over to level a playground. find the area of the playground in square m?

differential calculus

1 Answer Available

Last Activity: 2 Years ago

Find dy/DX when y=x^sinx+sin-1√x.

Please give me the solution of this problem.

differential calculus

0 Answer Available

Last Activity: 2 Years ago

If domain of f(x) is [-1, 2], then find the domain of f([x]-x^2+4), where [ ]denotes greatest integer function.

differential calculus

0 Answer Available

Last Activity: 2 Years ago

Solve the differential equation y’’+2ty’-4y=1, y(0)=y’(0)=0.

differential calculus

0 Answer Available

Last Activity: 2 Years ago

Example 20. (i) In a AABC, find the maxima and minima of u = sin A sin B sin C
where A + B + C = T
(ii) In a plane triangle ABC, find the maximum value of cosA cosB cosC.

differential calculus

0 Answer Available

Last Activity: 2 Years ago

View all Questions