find the greatest and least value of (sin^-1 x)^2+(cos^-1x)^2
@ganeshie8
you'll get help if your face isn't that scary looking
f'(x)=0 x=tan1
just an observation : max value occurs when x=+-1
boundaries. for min value we may have to differentiate. there seems to be no shortcut
but in exam we have to write n show ,evt,4 marker question..we just cant write observation based answers ;/
ok, set f'(x) = 0 and find the critical points
x=tan1
http://www.wolframalpha.com/input/?i=differentiate+%28arcsinx%29%5E2%2B%28arccosx%29%5E2+%3D0 so x=tan1
why do you set it =0?
after take derivative, set it =0 to get the critical points, but at the original input, you set the problem =0, why?
so if the curve is parallel to x axis somewhere we can know the point and then observe it from its LHL and RHL
i did it after taking derivative only
asin(x) = acos(x) x = 1/sqrt(2)
http://www.wolframalpha.com/input/?i=differentiate+%28arcsinx%29%5E2%2B%28arccosx%29%5E2+ equate it to 0 now,same thing
thats ur oly critical point for the potential min/max
you need to check your function at below :- 1) x = 1/sqrt(2) 2) domain extremes (boundaries)
Max f = max{ f(1/sqrt(2), f(-1), f(1) } Min f = min{ f(1/sqrt(2), f(-1), f(1) }
thanks!
np :)
one thing i wana point out asin/acos is NOT atan
yes..:|
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