ax4+35+ax6=ax5+ax10
Tính giá trị của a:
a x 4+35+a x 6=ax5+ax10
a×4+35+a×6=a×5+a×10
⇔a×4+a×6-a×5-a×10=-35
⇔a×(4+6-5-10)=-35
⇔a×(-5)=-35
⇔a=-35:(-5)
⇔a=7
Vậy a=7.
Cho hệ pt :
ax+by =3
ax2+by2=5ax2+by2=5
ax3+by3=9ax3+by3=9
ax4+by4=17ax4+by4=17
Tính
ax5+by5,ax2013+by2013=?ax5+by5,ax2013+by2013=?
Với giá trị nào của a thì:
a/ax5<1 b/ax6<20 c/250:a<5
a*5<1 <=> a<1/5
a*6<20 <=> a<10/3
205/a<5 <=> a< 41
a)Có ax5 < 1
=>a <1:5
a<1/5
b) ax6<20
=>a<20:6
a<20/6
c) 250:a<5
=>a<250:5
a<41
a/ a<= 0
b/a<=3.,3
c/a<=49
a, ( 300-150x2):(1+2+3+...+2021)
b , (312:13-24):(26x7-8)x2022
c .( ax10-90xa:9)x(ax2004+2013)
a) (300 - 150 × 2) : (1 + 2 + 3 + ... + 2021)
= (300 - 300) : (1 + 2 + 3 + ... + 2021)
= 0 : (1 + 2 + 3 + ... + 2021)
= 0
b) (312 : 13 - 24) : (26 × 7 - 8) × 2022
= (24 - 24) : (26 × 7 - 8) × 2022
= 0 : (26 × 7 - 8) × 2022
= 0 × 2022
= 0
c) (a × 10 - 90 × a : 9) × (a × 2004 + 2013)
= (10a - 90a : 9) × (a × 2004 + 2013)
= (10a - 10a) × (a × 2004 + 2013)
= 0 × (a × 2004 + 2013)
= 0
a)
\(\text{ ( 300-150x2):(1+2+3+...+2021)}\)
= \(0:(1+2+3+...+2021)\)
= \(0\)
b)
\(\text{ (312:13-24):(26x7-8)x2022}\)
\(=0:(26x7-8)x2022\)
\(=0:174x2022\)
\(=0\)
c)
( ax10-90xa:9)x(ax2004+2013)
= ( 10a-10a) x (ax2004+2013)
= 0 x (ax2004+2013)
= 0
\(\text{a) (300 - 150 × 2) : (1 + 2 + 3 + ... + 2021)}\)
\(=\dfrac{300-300}{1+2+3+...+2021}=\dfrac{0}{1+2=3+...+2021}=0\)
\(\text{b) (312 : 13 - 24) : (26 × 7 - 8) × 2022}\)
\(\text{=(24 - 24) : (26 × 7 - 8) × 2022}\)
\(\text{= 0 : (26 × 7 - 8) × 2022}\)
\(=0\)
c)\(\text{ (a × 10 - 90 × a : 9) × (a × 2004 + 2013) }\)
\(\text{= (10a - 90a : 9) × (a × 2004 + 2013)}\)
\(\text{= (10a - 10a) × (a × 2004 + 2013) = 0 × (a × 2004 + 2013) = 0}\)
Ax7+Ax9-A-Ax5=290
A x 7 + A x 9 - A - A x 5 = 290
A x 7 + A x 9 - A x 1 - A x 5 = 290
A x ( 7 + 9 - 1 - 5 ) = 290
A x 10 = 290
A = 290 : 10 = 29
A x 7 + A x 9 - A - A x 5 = 290
A x 7 + A x 9 - A x 1 - A x 5 = 290
A x ( 7 + 9 - 1 - 5 ) = 290
A x 10 = 290
A = 290 : 10
A = 29
125<ax6<130
(1,5 điểm) Tính
aa ¯ :ax5+45
aa ¯ :ax5+45 = 11 x 5 + 45 = 55 + 45 = 100
tim a biet:ax3+ax6-a-1968=3680
ax3+ax6-a-1968=3680
ax3+ax6-ax1-1968=3680
ax(3+6-1)-1968=3680
ax8=3680+1968
ax8=5648
a=5648:8
a=706
a x 3 + a x 6 - a -1968 = 3680
a x ( 3 + 6 ) - a -1968 = 3680
a x 9 - a - 1968 = 3680
a x 8 - 1968 = 3680
a x 8 = 3680 + 1968
a x 8 = 5648
a = 5648 : 8
a = 706