Toán Lớp 7: Bài 1 Tìm x biết a, 2^x = 16 b,(x/13)^2 = 49/169 c,(-2/3)^x = -8/27 d,(-1/5)^x = (-1/125)^3 e, x^4 = -16/625 f, (3/4)^x = 2^8/3^4 Làm h

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Toán Lớp 7:  Bài 1 Tìm x biết a, 2^x = 16 b,(x/13)^2 = 49/169 c,(-2/3)^x = -8/27 d,(-1/5)^x = (-1/125)^3 e, x^4 = -16/625 f, (3/4)^x = 2^8/3^4 Làm hộ nhé

tuyetanhthu · Answer

Đề b&agrave;i: a, 2^x = 16 b,(x/13)^2 = 49/169       c,(-2/3)^x = -8/27 d,(-1/5)^x = (-1/125)^3      e, x^4 = -16/625 f, (3/4)^x = 2^8/3^4     a, 2^x = 16     =>2^x=2^8     =>x=8     b,(x/13)^2 = 49/169     =>x^2/169=49/169     =>x^2=7^2     =>x=7     c,(-2/3)^x = -8/27     =>(-2/3)^x=(-2/3)^3     =>x=3

diepbich93 · Answer

C&aacute;c bước giải:    a, 2^x = 16     =>2^x=2^8     =>x=8     b,(x/13)^2 = 49/169     =>x^2/169=49/169     =>x^2=7^2     =>x=7     c,(-2/3)^x = -8/27     =>(-2/3)^x=(-2/3)^3     =>x=3     d,(-1/5)^x = (-1/125)^3     =>(-1/5)^x = (-1/5)^9     =>x=9     e, x^4 = -16/625     =>x^4=-(4/5)^4     =>x=-4/5     f, (4/3)^x = 2^8/3^4     =>(4/3)^x =(4/3)^4     =>x=4