Question

Answer 1

a. <=> 2x<7-5

<=>2x<2

<=>x<1

S={x/x<1}

b. <=> -2x<5+1

<=> -2x<6

<=>x> -3

S={x/x>-3}

c. <=> 4x-8>9x-3-2x+1

<=>4x-9x+2x>-3+1+8

<=> -3x> 6

<=>x< -2

S={x/x<-2}

d. <=>x²-2x- x²-2x-x-2<12

<=> x²-2x-x²-2x-x<12+2

<=> -5x<14

<=> x> \(\dfrac{-14}{5}\)

S={x/x>\(\dfrac{-14}{5}\)}

e. <=> 4(2x+2) + 3.2< 5(3x-2)

<=> 8x+8 +6< 15x-10

<=>8x-15x<-10-6-8

<=> -7x<-24

<=>x>4

S={x/x>4}

Trục số bạn tự vẽ nhé.