@JS-M said:1 ??
bhai u know the rule of forum u must post the answer along with explanation
if x = tan 15 than x^2+1/x^2 = ?
@pathakrahul said:bhai u know the rule of forum u must post the answer along with explanation
.......yr confrm kar raha tha.....we knw from statement x^2-x+1=0
now x^9(x^3+1)+x^3(x^3+1) +1
x^3+1 = (x+1)(x^2-x+1).......which z zero......so ans z 1
@pathakrahul said:bhai u know the rule of forum u must post the answer along with explanation
You'll get two factors of (x^3+1) and one constant 1 by solving the given expression.
And now, as per the given relation x+1/x = 1, we have x^2-x+1 = 0
Hence, terms having x^3 + 1 will turn out to be zero leaving answer as 1. :D
@pathakrahul said: if x = tan 15 than x^2+1/x^2 = ?
We know that tan 15 = 2 - _/3
Hence, x^2 = 7 - 4_/3
So solving x^2 - 1/x^2 = 14 [Answer]. :D
a man borrowed 40000 at a interest of 8% si per yr.at the end of second year he paid back certain amount and at the end of fifth year he pad back rs 35960 and cleared the debt. what is the amount did he paid back after 2 year
@Estallar12 said:We know that tan 15 = 2 - _/3Hence, x^2 = 7 - 4_/3So solving x^2 - 1/x^2 = 14 [Answer].
bhai if any person dont know the value of tan 15 then what one should do........
@pathakrahul said:bhai if any person dont know the value of tan 15 then what one should do........
tan(45-30)
@pathakrahul said: if x = tan 15 than x^2+1/x^2 = ?
x=tan15=tan(45-30) = (1-1/3^2)/(1+1/3^2) = (3^2-1)/(3^2+1)
therefore x+1/x = 4..square both sides x^2+1/x^2 + 2= 16 => x^2+1/x^2 = 14
@pathakrahul said:bhai if any person dont know the value of tan 15 then what one should do........
Use the identity of tan(A-B) = tan(45-30) = [tan45 - tan30]/ 1 + tan45*tan30
You will get a Irrational Fraction. You can either rationalise it and find x^2 and solve.
Or else just find x+1/x using it and then square it and subtract two from it as (x+1/x)^2 = x^2 + 1/x^2 + 2. :D
kindly explain....
@pathakrahul said: a man borrowed 40000 at a interest of 8% si per yr.at the end of second year he paid back certain amount and at the end of fifth year he pad back rs 35960 and cleared the debt. what is the amount did he paid back after 2 year
20,040????
@anubhav2011 said:20,040????
bhai soln or explanation.........cant say bcoz none of these is also in opn
@pathakrahul said: a man borrowed 40000 at a interest of 8% si per yr.at the end of second year he paid back certain amount and at the end of fifth year he pad back rs 35960 and cleared the debt. what is the amount did he paid back after 2 year
13,736....??