ively ▁being ▁maintained . ▁Red uce ▁became ▁free ▁software ▁in ▁ 2 0 0 8 . ▁As ▁of ▁today , ▁the ▁most ▁popular ▁commercial ▁systems ▁are ▁Mathemat ica ▁and ▁Map le , ▁which ▁are ▁commonly ▁used ▁by ▁research ▁mathemat icians , ▁scient ists , ▁and ▁engine ers . ▁Fre ely ▁available ▁alternatives ▁include ▁S age Math ▁( which ▁can ▁act ▁as ▁a ▁front - end ▁to ▁several ▁other ▁free ▁and ▁non free ▁C AS ). ▁ ▁In ▁ 1 9 8 7 , ▁H ew lett - Pack ard ▁introduced ▁the ▁first ▁hand - h eld ▁calcul ator ▁C AS ▁with ▁the ▁H P - 2 8 ▁series , ▁and ▁it ▁was ▁possible , ▁for ▁the ▁first ▁time ▁in ▁a ▁calcul ator , ▁to ▁ar range ▁algebraic ▁expressions , ▁different iation , ▁limited ▁symbol ic ▁integration , ▁Taylor ▁series ▁construction ▁and ▁a ▁sol ver ▁for ▁algebraic ▁equations . ▁In ▁ 1 9 9 9 , ▁the ▁independently ▁developed ▁C AS ▁E rable ▁for ▁the ▁H P   4 8 ▁series ▁became ▁an ▁officially ▁integrated ▁part ▁of ▁the ▁firm ware ▁of ▁the ▁emer ging ▁H P   4 9 / 5 0 ▁series , ▁and ▁a ▁year ▁later ▁into ▁the ▁H P ▁ 4 0 ▁series ▁as ▁well , ▁whereas ▁the ▁H P ▁Prime ▁adopted ▁the ▁X cas ▁system ▁in ▁ 2 0 1 3 . ▁ ▁The ▁Texas ▁Inst ru ments ▁company ▁in ▁ 1 9 9 5 ▁released ▁the ▁T I - 9 2 ▁calcul ator ▁with ▁a ▁C AS ▁based ▁on