On the valence of the sum of two convex functions

Styer, D.; Wright, D.

doi:10.1090/S0002-9939-1973-0313495-2

On the valence of the sum of two convex functions
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Proc. Amer. Math. Soc. 37 (1973), 511-516 Request permission

Abstract:

In this paper it is shown that the sum of two starlike functions may have an infinite number of zeros and that the sum of two convex functions may be at least three-valent. Furthermore, the convex sum of two odd convex functions is studied.

References

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Classical function theory problems

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