CBSE Class 12 Sample Paper for 2021 Boards

Class 12
Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Find the intervals in which the function π given by π(π₯) = tan π₯ β 4π₯, π₯ β (0,Ο/2) is (a) strictly increasingΒ Β Β Β Β  (b) strictly decreasing

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Question 32 Find the intervals in which the function π given by π(π₯) = tan π₯ β 4π₯, π₯ β (0,π/2) is (a) strictly increasing (b) strictly decreasing π(π₯) = tan π₯ β 4π₯ Finding π^β² (π) π^β² (π₯)=γπ ππγ^2 π₯ β4 Putting π^β² (π) = 0 γπ ππγ^2 π₯ β4=0 γπ ππγ^2 π₯=4 γπ ππγ^2 π₯=2^2 πππ π=Β±π Thus, π=π/π,ππ/π,ππ/π,β¦β¦β¦ Since π₯ β (0,π/2) β΄ π= π/π Plotting points on Number line Hence, π(π₯) is is strictly decreasing in (π,π/π) & π(π₯) is strictly increasing in (π/π,π/π)