if the tangent at any point on the curve y=x^3+kx^2+x+5, x belongs to R, makes an acute angle with x-axis, then which of the following is correct??
A)k

Question

if the tangent at any point on the curve y=x^3+kx^2+x+5, x belongs to R, makes an acute angle with x-axis, then which of the following is correct??
A)k<1 B)k<3^1/2 C)0<k<3 D)k belongs to (0,1)

amistre64 · Answer

a poly is one of the most basic function to take a derivative of .....

anonymous · Answer

but what will i do after finding the derivative???

amistre64 · Answer

an acute angle has a value between 0 and 90,  the slope of a line is also the tangent of an anlge

amistre64 · Answer

in other words,  slope <=0

amistre64 · Answer

ugh ... slope >= 0

amistre64 · Answer

y= x^3+kx^2+x+5

y'= 3x^2+2kx+1 >= 0

anonymous · Answer

oh...got it! thnx...

amistre64 · Answer

:)  good luck