···Concavity of curve. Concave down and concave up. Second derivative tangent lines of function. Mathematics resources for teachers and students.RFID:Image ID:2RCX8YNPreviewSaveShareBuy the printImage detailsContributor:SAMYA JAKANE / Alamy Stock VectorImage ID:2RCX8YNReleases:Model - no | Property - noDo I need a release?