very good observation
and in fact your answer is correct ...
I would give a slightly better way
rewrite the equn as
(sin x)^4 - 2 = (sin x)^5 + (cos x)^5
now the max value of LHS is -1
and the min value of RHS = -1
thus if the equation holds true ... both the sides are got to be equal to -1
hence u can come to the solution ...
you found out D .... but in the ques you need to find out the sum of digits of D ... which turns out to be 1+0 = 1
i ll give u the last and most important hint:
let E = sum of digits of D
find a way to prove that E would be a single digit number
then u can easily say that E would be 1
if the digital root of a number is 1 and the number is single digit number ... then the number is got to be 1
The sum of the digits of 199 = 19 = 1 because 199 is congruent to 1 mod 9
if A = 199
den b = sum of digits of A = 10 (not 1)
(by expanding this number, I assumed you didn't want to sum it again else B=1 C=1 D=1)
u r absolutely right here ... i didn't want it to sum it again.
This is as far as I follow the problem please provide more guidance.
u r absolutely correct here ... u followed it absolutely correctly...
HINT: Prove that sum of digits of D will be a single digit number
if u find that sum of digits of D will be a two digits number ... then the ans may be one of... 19,28,37,46,55,64,73,82,91
coz all of the above two digit numbers are congruent to 1 under MOD 9 ....
but if the sum of digits of D is a single digit number then the answer will be 1 .... i hope u get wot i say
Milan uses an escalator at the railway station.
If he runs up 8 steps of the escalator, then it takes him 40.0 seconds to reach the top of the escalator.
If he runs up 15 steps of the escalator, then it takes him only 22.5 seconds to reach the top of the escalator.
How many seconds would it take Milan to reach the top, if he did not run up any steps of the escalator at all? Also, how many steps are visible, when the escalator is stationary?
i never disrespect anyone ... i can understand how u feel ..... u know her for long .... but she took against me for a long tym ... and i respect those ppl who returns the same to me ... as long as i am here in this forum ... she in no way will earn respect back from me .. for example here u were solving the problem ... u didn't have ne issues ... once i told u to read the statements properly ... nd btw ... OR here in no way meant that it can be div by both ... u cannot implicitly arrive to a conclusion of ur own .... she can teach me math ... but can't teach me logic and interpretations ....
and even if i am wrong .... she shud have the MANNERS to tell me .... if she doesn't have ... she better learn it from somewhere