Evaluate :
(i) (−5)∘(ii) 8∘+4∘+2∘(iii) (8+4+2)∘ (iv) 4x∘(v) (4x)∘(vi) [(103)∘]5(vii) (7x∘)2(viii) 9∘+9−1−9−2+912−9−12
We know that a∘=1
(i) (−5)∘=1 (∵ a∘=1)(ii) 8∘+4∘+2∘=1+1+1=3 (∵ a∘=1)(iii) (8+4+2)∘=(14)∘=1 (∵ a∘=1)(iv) 4x∘=4×1=4(v) (4x)∘=1(vi) [(103)∘]5=10∘=1(vii) (7x∘)2=72×x0×2=49×1=49(viii)9∘+9−1−9−2+912−9−12=1+19−192=(32)12−(32)−12=1+19−181+32×12−32×(−12)=1+19−181+3−3−1=1+19−181+31−13=81+9−1+243−2781=333−2881=30581=36281