(x-1).(x+2) > (x-1)2 + 3
\(\Leftrightarrow\)(x-1).(x+2) - (x-1)2 >3
\(\Leftrightarrow\)(x-1).(x+2) - (x-1)(x-1)> 3
⇔(x-1).[(x+2) - (x-1)]> 3
⇔(x-1).[x+2 - x+1]> 3
⇔3.(x-1)> 3
⇔3x - 3 >3
⇔3x > 3+3
⇔3x > 6
⇔x > 2
(x-1).(x+2) > (x-1)2 + 3
\(\Leftrightarrow\)(x-1).(x+2) - (x-1)2 >3
\(\Leftrightarrow\)(x-1).(x+2) - (x-1)(x-1)> 3
⇔(x-1).[(x+2) - (x-1)]> 3
⇔(x-1).[x+2 - x+1]> 3
⇔3.(x-1)> 3
⇔3x - 3 >3
⇔3x > 3+3
⇔3x > 6
⇔x > 2
Giup em voi a
Giai cac bat phuong trinh sau va bieu dien tap nghiem cua bat phuong trinh tren truc so:
a. 2(3x-1)-2x<2x-1
b. 4x-8≥3(3x-2)+4-2x
c. 3(x-2)(x+2)<3x²+x
d. (x+4)(5x-1)>5x²+16x+2
Giai cac bpt sau va bieu dien tap nghiem tren truc so
a)x2\(\ge\)0
b)x2\(\le\)0
c) x2-2x+3 \(\ge\)0
1. so nghiem cua da thuc x2(x2-x+1)+5(x2-x)+5 la
2.so nghiem cua da thuc x4-x3+x2-x la
3.tap hop cac gia tri cua x \(\ne\)0 thoa man x+x2-x3-x4= 0 S={...}
giai bat phuong trinh va bieu dien ngiem tren truc so
x(x^2+2) > x^3-x+6
1.so nghiem cua da thuc x4-x3+x2x la
2.viet so 1993-199 duoi dang tich cua 3 so tu nhien lien tiep so be nhat trong 3 so tu nhien do la
3.tap hop cac gia tri cua x\(\ne\)0 thoa man x3-4x=0 la S(...)
2/3-x>0.tap nghiem la?
1.cho tam giac ABC vuong tai A , AB =3cm ,AC=4cm. Ke AH vuong goc BC, D va F lan luot la diem doi xung cua H qua AB va AC . Khi do độ dai DE=?
2.so nghiem cua da thuc x^(x^2-x+1)+5(x^2-x)+5 la
3. so nghiem cua da thuc x^4-x^3+x^2-x la
cau 1 giai phuong trinh sau
a) 7 x -14 =0
b) ( 3x +1 ) ( 2x-2) =0
c) ( 3x -1 ) = x-2
cau 2 giai bat phuong trinh va bieu dien truc nghiem tren truc so
a ) 2x+5 < hoac ( = )9
b) 3x +4 <5x-3
c ) 3x-1 tren 4 >2
cau 3 cho tam giac a bc vuong goc tai a , co ab = 12 cm , ac =16 cm . ke duong cao ah ( hthuoc bc )
a) chung minh : tam giac hba thuoc tam giac abc
b) tinh do dai bc,ah
c) he ad,de,df,la phan giac lan luot cua cac goc bac,hdb,adc,c thuoc a b , d thuoc bc, f thuoc ab
chung minh rang : ea phan eb = db phan dc , fc phan fa = 1
ban nao nhanh minh k cho 10 k
Chao ae , thay co
cau 1 (1d) x-5=0
<=> x=5
nhung minh quen ghi vay tap nghiem cua pt , ae vs thay co nghi xem minh Bao nhiu diem