Let f(x)= integral of (t^2+2t+2)dt within limits 0 to x where x is set of real numbers satisfying the inequation log(1+√6x-x^2-8)>=0. If f(x)€[a,b] then maximum value of |a-b| is
@freckles
@ikram002p
You could start by solving the integral. Also consider: \[\log(X) \ge 0 \]is true when \[X \ge 1\] for real numbers.
That gives me x€[2,4]
For the condition of log to be greater than
0
Is it sqrt(6)x or sqrt(6x) in your inequality?
The surd is over the whole term 6x-x^2-8 whole of if
It*
x€[2,4] is correct for the inequality, yes..
since g(t)=t^2+2t+2 is an increasing function and all above the x-axis then the area in increasing as we move to the right of x=0 Since x can only be between x=2 and x=4 then that would mean that \[\int\limits_0^2 g(t) dt \le f(x) \le \int\limits_0^4 g(t) dt\] so you will find a and b by evaluating both of those integrals I believe
that is increasing function on the interval [0,4] which is all we need to be concerned with
of course it is increasing elsewhere but that is the only interval as I said we should be worried about
Bt when we r gonna solve the integral won't there come a constant ... How to evaluate its value?
@ganeshie8
@hartnn
I'm not sure what you are asking
we already know that \[f(x) \in [\int\limits_0^2 g(t) dt, \int\limits_0^4 g(t) dt]\] so you already know your a and b you just have to evaluate those integrals
g(t) was equal to your integrand g(t)=t^2+2t+2
It's integration is t^3/3 + t^2 + 2t +c what about the value of c?
you have a definite integral
not an indefinite
Oops !! Forgot that sorry for asking a stupid question as that!! Thanks also
however you could put plus C in but the C's are just going to cancel out when you do the subtraction part
\[a=[\frac{t^3}{3}+t^2+2t]_0^2 =? \\ b=[\frac{t^3}{3}+t^2+2t]_0^4=?\]
a=32/3 Ans b=136/3
And*
@freckles thankyou
np
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