The acute accent is on the first syllable of yuṣmad and asmad in the Genitive Singular.,
This applies when the forms are मम and तव, and not मे and ते ॥ Thus म꣡म स्वम्, त꣡व स्वम् ॥ The word युष्मद् and अस्मद् are derived from युष and अस by adding the affix मदिक् (Un I. 139) युष्मद् + ङस् = युष्मद् + अश् (VII. I. 27) = तव अट् + अश् 6.2.96 = तव꣡ + अ꣡श् 7.2.90 = तव (VI. I. 97). Here by 8.2.5, व would have been udatta, the present sutra makes त udatta. So also with मम ॥,