Question

+ ka Avishkar kab howa

Answer 1

pata nhi ...kisi n bataya nhi

Answer 2

hey brother
here is ur answer
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It's unknow when kate invented thesymbol. Robert Recorde also introduced the modern use of minus to the UK in 1557. The first appearance of the minus sign was by Johannes Widmann in 1489. It was found in his book called "Mercantile Arithmetic

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I hope this will help✌
#Prem