61 - Calculus Questions Answers
d/dx((1+x^2+x^4)/(1+x+x^2))=ax+b
then a=?, b=?
1+x2+x4 = (1+x+x2)(1-x+x2)
now solve
Find a formula for a function g(x) satisfying the following conditions
a) domain of g is (-∞ , ∞ ) b) range of g is [-2 , 8] c) g has a period π d) g(2) = 3
g(x) = 3-5sin(2x-4)
Let f(x) = x135 + x125 - x115 + x5 +1. If f(x) is divided by x3-x then the remainder is some function of x say g(x). Find the value of g(10)
for getting reminder put x3= x so
x135 + x125 - x115 + x5 +1 will give
x45 + x41*x2 - x38*x +x*x2 +1
x15 + x13*x2*x2 - x12*x2*x +x*x2 +1
x17 + x3 +1
x5*x2 + x + 1
x7 + x + 1
x2*x + x +1
x3 + x +1
x+x+1
2x+1
now put x = 10
How to inegrate ( In t) dt /(t-1)
let lnt = x so dt/t = dx so dt = tdx = exdx
now ∫(ln t)dt/(t-1) = ∫xexdx/(ex-1) = ∫x(ex-1+1)dx/(ex-1)
now solve
∫√tanx
let √tanx = t
so sec2xdx/2√tanx = dt
so (1+t4)dx/2t = dt
so dx = 2tdt/(1+t4)
now solve
if ƒ:R−{0} -> R, 2ƒ(x) − 3ƒ(1⁄x) = x² then ƒ(3)= ?
2ƒ(x) − 3ƒ(1⁄x) = x² (1)
so 2ƒ(1/x) − 3ƒ(x) = 1/x² (2)
multiply (1) to 2 and (2) to 3, then add the two equations, you will get f(x) then calculate f(3)
Sir/Madam,
Suddenly a question struck on my mind: 0×∞= 1 or 0?? as 1⁄0=∞.
it will be 0, assume it by considering that ∞ is a big number
for ex. 0*(1111111111111111111111111) = 0
FIND DOMAIN OF f(x)=log4log3 log2x WHERE 4,3,2 ARE BASES ?
f(x)= log4log3log2x
so 0 < log3log2x < ∞
so 1 < log2x < ∞
so 2 < x < ∞
let us consider the case of ellipse with x and y axes as their axes
eq. is x2/a2 + y2/b2= 1
on differentiating we get 2x/a2 + 2yy'/b2 = 0 y'is first differential
so yy'/x = -b2/a2
again differentiate and get answer.
You should remember that you should differentiate as many times as the number of constants.
for ex. in the case of parabola only first diffrentiation is sufficient.
now complete it for all conics
using the transformation x=r cosθ and y=r sinθ,find the singular solutionof the differential equation x+py=(x-y)(p2+1)½ where p=dy/dx
x=rcosθ and y=rsinθ
so dx=-rsinθdθ and dy = rcosθdθ
so p = -cotθ
so given eq. will become x-cotθy = (x-y)cosecθ
on putting values of x and y we get
0 = r(cosθ-sinθ)/sinθ
so tanθ = 1 so θ = nπ+π/4
so x = rcos(nπ+π/4) and y = rsin(nπ+π/4)