MEDIUM
JEE Main
IMPORTANT
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Let fx be a twice differentiable function in a,b, given that fx and f"x has same sign in a,b.
Statement I: f'x=0 has at the most one real root in a,b.
Statement II: An increasing function can intersect the x-axis at the most once.

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Important Questions on Monotonicity, Maxima and Minima

MEDIUM
JEE Main
IMPORTANT
Let u=c+1-c and v=c-c-1, c>1 and let fx=ln1+x,x-1,.
Statement I: fu>fv,c>1 because
Statement II: fx is increasing function, hence for u>v, f(u)>f(v).
MEDIUM
JEE Main
IMPORTANT

For the following questions, choose the correct answers from the codes (a), (b), (c) and (d) defined as follows:
Let f0=0,fπ2=1,f3π2=-1 be a continuous and twice differentiable function.
Statement I: f'x1 for atleast one x0,3π2 because
Statement II: According to Rolle's theorem, if y=gx is continuous and differentiable xa,b and ga=gb, then there exists atleast one c such that g'c=0.

MEDIUM
JEE Main
IMPORTANT
For the following questions, choose the correct answers from the codes (a), (b), (c) and (d) defined as follows:
Statement I: For any ΔABC, sinA+B+C3sinA+sinB+sinC3.
Statement II: y=sinx is concave downward for x0,π.
MEDIUM
JEE Main
IMPORTANT
For the following questions, choose the correct answer
Statement I: If fx=xsinx+cosx-1
(where [.] denotes the greatest integer function), then f'x=xcosx-sinx for any x integer.
Statement II: f'x does not exist for any x integer.
EASY
JEE Main
IMPORTANT

For the given questions choose the correct answer from the given options defined as follows:


fx is a polynomial of degree 3 passing through origin having local extrema at x=±2.

Statement I: Ratio of area in which fx cuts the circle x2+y2=36 is 1:1.

Statement II: Both y=fx and the circle are symmetric about origin.

HARD
JEE Main
IMPORTANT
A particular substance is being cooled by a stream of cold air (temperature of the air is constant and is 5oC), where rate of cooling is directly proportional to square of difference of temperature of the substance and the air. If the substance is cooled from 40oC to 30oC in 15 min and temperature after 1 hour is ToC, then find the value of T2, where [.] represents the greatest integer function.
MEDIUM
JEE Main
IMPORTANT
Find the coordinates of the point on the parabola y=x2+7x+2 which is closest to the straight line y=3x-3.