[FONT="]There is the following equation: [/FONT]
[FONT="]x^2+2(ma)x+3am2=0  a,m ∈ R[/FONT]
[FONT="]a) Find a such that the euation has real roots, ∀ m ∈ R.[/FONT]
[FONT="]b) Find m such that the euation has real roots, ∀ a ∈ R.[/FONT]
[FONT="]I put the condition: DELTA >= 0[/FONT]
[FONT="]I found DELTA but since this step I have problems..[/FONT]
[FONT="]Sorry for my english!
The answer should be: a <= sqrt(8/21) ; m <= sqrt(8/21)
My try:
[/FONT]
[FONT="]x^2+2(ma)x+3am2=0  a,m ∈ R[/FONT]
[FONT="]a) Find a such that the euation has real roots, ∀ m ∈ R.[/FONT]
[FONT="]b) Find m such that the euation has real roots, ∀ a ∈ R.[/FONT]
[FONT="]I put the condition: DELTA >= 0[/FONT]
[FONT="]I found DELTA but since this step I have problems..[/FONT]
[FONT="]Sorry for my english!
The answer should be: a <= sqrt(8/21) ; m <= sqrt(8/21)
My try:
[/FONT]
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