\(\text{25-(9-10)+(28-4)}\\ =25-9+10+28-4\\ =16+10+28-4\\ =26+28-4\\ =54-4\\ =50\)
\(\text{25-(9-10)+(28-4)}\\ =25-9+10+28-4\\ =16+10+28-4\\ =26+28-4\\ =54-4\\ =50\)
d/ khó lắm đó nha. ai biết minh tích
38/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - ............. + 197/4851 - 199/4950.
2. ( x + 1 ) + ( x + 4 ) + ( x + 7 ) + ......... + ( x + 28 ) = 155
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30=
A = \(\dfrac{28}{25}\) + \(\dfrac{9}{10}\) - \(\dfrac{11}{15}\) + \(\dfrac{13}{21}\) - \(\dfrac{15}{28}\) + \(\dfrac{17}{26}\) - ... + \(\dfrac{197}{4851}\) - \(\dfrac{199}{4950}\)
38/25+9/10-11/15+13/21-15/28+17/36-19/45+21/55=
Câu 10. Cho (1 − 1/4) x (1 − 1/9) x (1 − 1/26 ) x (1 − 1/25 ) x (1 − 1/36 ) x (1 − 1/49 ) x (1 − 1/64 ) = , biết là phân số tối giản. Tính = + . A. = 28 B. = 25 C. = 30 D. = 36 mik can gap
S = 38/25 + 9/10-11/15+13/21+15/28+17/36-19/45 +...-199/4950
Tính tổng : A=38/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - ................+197/4851-199/4950
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+149+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39*100
Thắng xếp các số thành 4 hàng ABCD như sauA 1, 8, 9, 16, 17, 24, 25, ...B 2, 7, 10, 15, 18, 23, 26,...C 3, 6,11, 14, 19, 22, 27, ...D 4, 5, 12, 13, 20, 21, 28, ...Hỏi số 2018 nằm ở hàng nào