152x2+135=?
Giải phương trình 4 + 15 2 x 2 - 5 x = 4 - 15 6 - 2 x
A. x = 3 2 ; x = 2
B. x = 3 2 ; x = - 2
C. x = - 3 2 ; x = - 3
D. x = - 3 2 ; x = 2
Đáp án A
4 + 15 2 x 2 - 5 x = 4 - 15 6 - 2 x ⇔ 4 + 15 2 x 2 - 5 x = 4 + 15 2 x - 6 ⇔ 2 x 2 - 5 x = 2 x - 6 ⇔ 2 x 2 - 7 x + 6 = 0 ⇔ x ∈ { 2 ; 1 ; 5 }
135+135-135*135/135=
135 x37 -135+64 x 135
=135(37+64-1)=135*100=13500
135 x 124 - 135 x 23 - 135
=135x (124-23-1)
=135 x 100
=13500
135 x 124 - 135 x 23 - 135
= 135 x 124 - 135 x 23 - 135 x 1
= 135 x ( 124 - 23 - 1)
= 135 x ( 101 - 1)
= 135 x 100
= 13500
( 135 * 269 - 133 ) - ( 135 * 269 -135 )
(135.269-133)-(135.269-135)
=(135.269-135.269)+(135-133)
=0+2
=2
135 x 80 + 20 x 135 = 135 c ( 80 c 20 )
Đáp án: 135 x 80 + 20 x 135 = 135 x ( 80 + 20 )
135 91 - 135 89 và 135 100 - 135 99
13591 - 13589 = 13589 x ( 1352 - 1 )
135100 - 13599 = 13599 x ( 135 - 1 ) = 13599 x 134 = 13589 x 13510 x 134 = 13589 x ( 13510 x 134 )
Có : 1352 - 1 < 13510 x 134
=> 13589 x ( 1352 - 1 ) < 13589 x ( 13510 x 134 )
=> 13591 - 13589 < 135100 - 13599
Ta có:
\(135^{91}-135^{89}=135^{89}\times\left(135^2-1\right)\)
\(135^{100}-135^{99}=135^{99}\times\left(135-1\right)=135^{99}\times134=135^{89}\times134=135^{89}\times\left(135^{10}\times34\right)\)
Có: \(135^2-1< 135^{10}\times134\)
\(\Rightarrow135^{89}\times\left(135^2-1\right)< 135^{89}\times\left(135^{10}\times134\right)\)
\(\Rightarrow135^{91}-135^{89}< 135^{100}-135^{99}\)
Vậy \(135^{91}-135^{89}< 135^{100}-135^{99}\)
Tính bằng cách thuận tiện nhất.
135 x 37 + 135 + 62 x 135
135 x 37 + 135 + 62 x 135
= 135 x 37 + 135 x 1 + 62 x 135
= 135 x ( 37 + 1 + 62)
= 135 x 100
= 13500
(-135).94+(-135).7+135