Zadanie 1a
Set a=−4. By varying b systematically or otherwise, find the two b values for which F has a repeated real root.
Zadania wzorowane na pytaniach z tego arkusza: te same umiejętności, format i punktacja, inne dane i kontekst. Treści arkusza IB nie publikujemy.
W bazie 14 zadań z tego arkusza, razem 55 punktów, każde z kluczem i schematem punktowania.
Set a=−4. By varying b systematically or otherwise, find the two b values for which F has a repeated real root.
For a=−4, state the b values giving (i) no x-axis intercepts; (ii) four distinct x-axis intercepts.
Now set a=4. State the b values giving (i) exactly one intercept; (ii) no intercepts; (iii) exactly two intercepts.
If F has four distinct x-axis intercepts, state where its local maximum and its two local minima lie relative to the x-axis.
For a<0, show that the stationary points are P = (0, b) and .
Assume a<0 and b>a²/4. For P = (0, b) and : (i) find F″ and classify each stationary point; (ii) state whether these points lie above or below the x-axis.
Assume a>0, so P=(0,b) is the only stationary point. (i) When b>0, state its type and position relative to the x-axis. (ii) For this positive a, state the condition on b placing P below the x-axis.
Prove that a<0 and 0<b<a²/4 imply exactly four distinct x-axis intercepts.
(i) Express the slope of y=kx² using only x,y. (ii) Hence show its orthogonal trajectories satisfy y′=−x/(2y). (iii) Solve this differential equation to show that these trajectories have equation x²+2y²=C, with constant C.
For a=4 and b=√5, sketch x2/25 + y2/16 = 1 and x2/4 − y2/5 = 1 on common axes. Label each curve and its x-intercepts. Intersection coordinates are not required.
Solve E_a and H_b simultaneously to show that their four intersections have coordinates , where the two signs are independent.
Show that E_a and H_b intersect orthogonally at their first-quadrant intersection M. You may use xM2 = (a2 + 9)(9 − b2)/9 and yM2 = a2b2/9.
Now take f=−2x/y and α=π/4, working locally where x>0, y≠0 and y+2x≠0. (i) Show that g=(y−2x)/(y+2x). (ii) Solve the homogeneous equation y′=(y−2x)/(y+2x) and give its general implicit form h(x,y)=d. You may use…
For a fixed finite nonzero f, use the rotation formula to prove .
Zapisujemy na Twoim urządzeniu to, bez czego serwis nie działa, np. zalogowanie. Plików analitycznych użyjemy tylko za Twoją zgodą. Szczegóły w polityce prywatności.