( 289 - 12 ) . ( 289 - 22) ... ( 289 - 202)
\(\dfrac{12-\dfrac{12}{7}-\dfrac{12}{289}-\dfrac{12}{85}}{4-\dfrac{4}{7}-\dfrac{4}{289}-\dfrac{4}{85}}=\)
\(=\dfrac{3.4-\dfrac{3.4}{4}-\dfrac{3.4}{289}-\dfrac{3.4}{85}}{4-\dfrac{4}{7}-\dfrac{4}{289}-\dfrac{4}{85}}=\dfrac{3.\left(4-\dfrac{4}{7}-\dfrac{4}{289}-\dfrac{4}{85}\right)}{1.\left(4-\dfrac{4}{7}-\dfrac{4}{289}-\dfrac{4}{85}\right)}=\dfrac{3}{1}=3\)
Tính M= ( căn 289-1)×(căn 289 -2)×( căn 289-3)×.......×(căn 289-100)
\(12-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}\) / \(4-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}\)
Tim B=81.((12-12/7-12/289-12/85)/(4-4/7-4/289-4/85))/((5+5/13+5/169+5/91)/(6+6/13+6/169+6/91)).158158158/711711711
Tim B=81.((12-12/7-12/289-12/85)/(4-4/7-4/289-4/85))/((5+5/13+5/169+5/91)/(6+6/13+6/169+6/91)).158158158/711711711
a) 3x + 2 . (-7) = 10
b) 25 -(30 + x) = - (27 - 8)
c) 15 - x = 12 - ( -14)
d) (4x + 11) - ( x + 34) = 67
e) 3 - 17 - x = 289 - (36 + 289)
a: =>3x=10+14=24
=>x=8
b: =>25-30-x=-19
=>-5-x=-19
=>x+5=19
=>x=14
c: =>15-x=12+14=26
=>x=-11
d: =>4x+11-x-34=67
=>3x-23=67
=>3x=90
=>x=30
e: =>-x-14=289-36-289=-36
=>x+14=36
=>x=22
a) 3x=24
x=8
b) 25-30-x=-19
25-30+19=x
14=x
c) 15-x=26
x=-11
d) 4x+11-x-34=67
3x=90
x=30
e) -14-x= -36
x=-14 -36
x= 22
tinh B
B=81.[12-12/7-12/289-12/85/4-4/7-4/289-4/85:5+5/13=5/169+5/91/6+6/13+6/169+6/91].158158158/711711711
giống bài mình cần mà ko có ai trả lời nhỉ
mong mọi người vô giúp 2 đứa mình với
B=81.(12.(1-1/7-1/289-1/85)/4.(1-1/7-1/289-1/85:5.(1+1/13+1/169+1/91)/6.(1+1/13+1/169+1/91).158158158/711711711
=81.(12/4:5/6).158.1001001/711.1001001
=81.18/5.158/711
=324/5
( 57 - 289 ) - ( 76 - 289 ) + ( 176 + 43 )
\(\left(57-289\right)-\left(76-289\right)+\left(176+43\right)\)
\(=\) \(\left(-232\right)\) \(-\) \(\left(-213\right)\) \(+\) \(219\)
\(=\) \(\left(-19\right)+219\)
\(=200\)
(57 - 289 ) - ( 76 - 289 ) + ( 176 + 43 )
= 57 - 289 - 76 +289 +176 +43
= (57 + 43 ) + ( -289 +289 ) + ( - 76 + 176 )
= 100 +100
=200
( 57 - 289 ) - ( 76 - 289 ) + ( 176 + 43 )=200
A=\(\cos^21+\cos^22+\cos^23+.......+\cos^287+\cos^288+\cos^289-\frac{1}{2}\)
B=\(\sin^21+\sin^22+\sin^23+....+\sin^287+\sin^288+\sin^289-\frac{1}{2}\)
C=\(\tan^21\times\tan^22\times\tan^23\times.....\times\tan^287\times\tan^288+\tan^289\)
D=\(\left(\tan^21\div\cot^289\right)+\left(\tan^22\div\cot^288\right)+......+\left(\tan^244\div\cot^246\right)+\tan^245\)
các bạn giúp mình với
tất cả các số đều có độ hết nha trừ cái 1/2 là không có dộ
\(A=cos^21+coss^22+...+cos^288+cos^289-\frac{1}{2}\)
\(A=1-sin^21+1-sin^22+...+1-sin^244+cos^245+cos^246+...+cos^289-\frac{1}{2}\)
\(A=1\cdot44+cos^245-\frac{1}{2}\)
\(A=44\)
B=\(sin^21+sin^22+...+sin^289-\frac{1}{2}\)
\(B=1-cos^21+1-cos^22+...+sin^245+sin^246+....+sin^289-\frac{1}{2}\)
\(B=1\cdot44+sin^245-\frac{1}{2}=44\)
\(C=tan^21\cdot tan^22\cdot...\cdot tan^288+tan^289\)
\(C=tan^21\cdot\left(tan^22\cdot tan^288\right)\cdot...\cdot\left(tan^244\cdot tan^246\right)\cdot tan^245+tan^289\)
\(C=tan^21+tan^289\approx3282\)
D = \(\left(tan^21:cot^289\right)+...+\left(tan^244:tan^246\right)+tan^245\)
\(D=\left(tan^21\cdot tan^289\right)+...+\left(tan^244\cdot tan^246\right)+tan^245\)
\(D=1+...+1+1\)
ta thấy từ 1 đến 89 có 89 số hạng, trong đó có 44 cặp.
vậy D = 45