if a^x= b^y = (ab)^(xy) prove that x+y =1

ln(a^x) = ln(b^y) = ln((ab)^(xy))
xln(a) = xyln(ab)
ln(a) = yln(ab) = y(ln(a) + ln(b))
y = ln(a)/(ln(a)+ln(b))
with same analysis for ln(b^y):
ln(b) = x(ln(a) + ln(b))x = ln(b)/(ln(a)+ln(b))
x + y = (ln(a) + ln(b))/(ln(a) + ln(b)) = 1

SC

Related Maths A Level answers

All answers ▸

Using a suitable substitution, or otherwise, find the integral of [x/((7+2*(x^2))^2)].


Show how you can rewrite (x+1)(x-2)(x+3) into the form of ax^3 + bx^2 + cx + d


If a curve has equation y = (-8/3)x^3 - 2x^2 + 4x + 18, find the two x coordinates of the stationary points of this curve.


Integral between 0 and pi/2 of cos(x)sin^2(x)