2^x+3^y=17
2^2x-3^(y+1)=5 (2^x)^2 - 3*3^y = 5
замена 2^x = t > 0
3^y = u > 0
t + u = 17
t^2 - 3u = 5
u = 17 - t
t^2 - 3*(17 - t) = 5
t^2 - 51 + 3t - 5 = 0
t^2 + 3t - 56 = 0
D = 9 + 4*56 = 233
t12=(-3 +- √233)/2
t1=(-3 - √233)/2 < 0 не рассматриваем
t2=(-3 + √233)/2 ≈ (-3 + 15.26)/2 ≈ 6.13
u = 17 - t = 17 - (-3 + √233)/2 = (34 + 3 - √233)/2 = (37 + √233)/2
обратная замена
2^x = t
2^x = (-3 + √233)/2
x = log(2) (-3 + √233)/2
3^y = u
3^y = (37 - √233)/2
y = log(3) (37 - √233)/2
красота страшная сила
Ответ (log(2) (-3 + √233)/2, log(3) (37 - √233)/2)
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Verified answer
2^x+3^y=17
2^2x-3^(y+1)=5 (2^x)^2 - 3*3^y = 5
замена 2^x = t > 0
3^y = u > 0
t + u = 17
t^2 - 3u = 5
u = 17 - t
t^2 - 3*(17 - t) = 5
t^2 - 51 + 3t - 5 = 0
t^2 + 3t - 56 = 0
D = 9 + 4*56 = 233
t12=(-3 +- √233)/2
t1=(-3 - √233)/2 < 0 не рассматриваем
t2=(-3 + √233)/2 ≈ (-3 + 15.26)/2 ≈ 6.13
u = 17 - t = 17 - (-3 + √233)/2 = (34 + 3 - √233)/2 = (37 + √233)/2
обратная замена
2^x = t
2^x = (-3 + √233)/2
x = log(2) (-3 + √233)/2
3^y = u
3^y = (37 - √233)/2
y = log(3) (37 - √233)/2
красота страшная сила
Ответ (log(2) (-3 + √233)/2, log(3) (37 - √233)/2)