here we go again :) - q7b ii) 2005 3uHSC: INV TRIG Q (1 Viewer)

[gamja]

[sorry in advance for potato webcam quality]

For q (ii), How would you explain that leading coefficient A being smaller lead to it having one solution?\

Also, I calculated and desmosd that there is indeed one sp being one of two solutions when A=(3sqrt3)/3, but if A<-(3sqrt3)/3, then there is more than one solution again...




help much appreciated

 

[cossine]

View attachment 37352
[sorry in advance for potato webcam quality]

For q (ii), How would you explain that leading coefficient A being smaller lead to it having one solution?\

Also, I calculated and desmosd that there is indeed one sp being one of two solutions when A=(3sqrt3)/3, but if A<-(3sqrt3)/3, then there is more than one solution again...

View attachment 37353
View attachment 37354

help much appreciated

So we don't consider the case when A<0 as per the question criteria. Think about what the curve will look like if there is only one root. This will give you an idea on how to perform the calculation.

 

[gamja]

So we don't consider the case when A<0 as per the question criteria. Think about what the curve will look like if there is only one root. This will give you an idea on how to perform the calculation.

so would you basically describe how decreasing the coefficient A 'flattens' out the curve and lifts the sp above the x axis; leaving one solution?

 

[cossine]

so would you basically describe how decreasing the coefficient A 'flattens' out the curve and lifts the sp above the x axis; leaving one solution?

Yes