I'm assuming the question asks for the values of k such that the equation has distinct real roots, or equal roots. If so just consider the discriminant, remember b2−4ac>0 for distinct real roots and b2−4ac=0 for equal roots (single root you may think of it as). In this case,a=2,b=−3 and c=−(k+1). If this isn't the question then please say what the actual wording of the full question was.
I'm assuming the question asks for the values of k such that the equation has distinct real roots, or equal roots. If so just consider the discriminant, remember b2−4ac>0 for distinct real roots and b2−4ac=0 for equal roots (single root you may think of it as). In this case,a=2,b=−3 and c=−(k+1). If this isn't the question then please say what the actual wording of the full question was.
The question is listed above, to find values of k and it says k has no real roots.
Sorry, I forgot to say...k has no real roots so its obviously 0 real roots but i don't really understand the above?
The value of the discriminant tells us how many real roots there are, and vice versa, the amount of roots tells us conditions which must hold for the discriminant (the one's above). Then we can use it to construct an inequality in terms of k and solve it.
yeah i thought to plug them in by labelling a,b and obviously c but how do you leave your answer?
As an inequality with k on one side and everything else on the other. The inequality is the range of values that k can take - as required by the question - in order to have no real roots.
As an inequality with k on one side and everything else on the other. The inequality is the range of values that k can take - as required by the question - in order to have no real roots.
silly me. now i got 9+8k-8 BUT, is it +8 because there is a negative sign infront of the bracket like this: -8-(k+1) ?
Sort of, it is hard to say from your specific working because you got distributed the negative weirdly, but be careful with the way you write them. The way you represented that would read as "minus 8 take away the quantity of k+1" which is not correct - it should be "minus 8 multiplied by the negative of the quantity k+1" so the negatives cancel and you get left with 8(k+1) hence +8. Just look at my working above.
Sort of, it is hard to say from your specific working because you got distributed the negative weirdly, but be careful with the way you write them. The way you represented that would read as "minus 8 take away the quantity of k+1" which is not correct - it should be "minus 8 multiplied by the negative of the quantity k+1" so the negatives cancel and you get left with 8(k+1) hence +8. Just look at my working above.
I understand. Thanks so much! yeah, i really need to take care with my negative signs tbh -8-(k+1) because - is infront of the bracket and infront of 8 it cancels because you are multiplying
thanks! so when i get questions like this it will see whether it has real roots or not and then i choose from the formula thing you sent first?
I understand. Thanks so much! yeah, i really need to take care with my negative signs tbh -8-(k+1) because - is infront of the bracket and infront of 8 it cancels because you are multiplying
thanks! so when i get questions like this it will see whether it has real roots or not and then i choose from the formula thing you sent first?
Essentially, yeah. Though you should probably understand where those specific restrictions come from.