HOC24
Lớp học
Môn học
Chủ đề / Chương
Bài học
Có, khi a = 0
\(B=\dfrac{11.3^{29}-3^{30}}{4.3^{28}}=\dfrac{3^{29}\left(11-3\right)}{3^{28}.4}=\dfrac{3.8}{4}=6\)
453 = (9.5)3 = 36.53
204 = (4.5)4 = 28.54
182 = (9.2)2 = 34.22
1805 = (4.9.5)5 = 210.310.55
\(=\dfrac{3^6.5^3.2^8.5^4.3^4.2^2}{2^{10}.3^{10}.5^5}=\dfrac{2^{10}.3^{10}.5^7}{2^{10}.3^{10}.5^5}=5^2=25\)
c.
321 = 3.320 = 3.(32)10 = 3.910
231 = 2.230 = 2.(23)10 = 2.810
>> 3.910 > 2.810
d.
2623 > 2523 = (52)23 = 546
12415<12515= (53)15 = 545
>> 12415 < 545 < 546 < 2623
e.
8016 = (23.10)16 = 248.1016
2821 = (22.7)21 = 224.721 = 224.75.716 < 224.85.716 = 224.(23)5.716 = 224.215.716 = 239.716 < 248.1016 = 8016
(22)3 > (22)1
a.a - [(a-1)(a+1)]
= [(a-1+1)a]-[(a-1)(a+1)]
= [(a-1)a + 1.a] - [(a-1)a + (a-1).1]
= (a-1)a + a - (a-1)a - (a - 1)
= a - a + 1
= 1
A= (298-1).299 = 298.299 - 299
B= 298.(299-1) = 298.299 - 298
==> A<B
A = 5a + 5b = 5(a+b) = 5.5 = 25
B = 5a + 5b + 13a +13b = 5(a+b) + 13(a+b) = 5.5 + 13.5
C = 23(a+b) - 12(a+b) = 23.5 - 12.5