If the angle between the vectors λi^−3j^+5k^ and 2λi^−λj^−k^ is an obtuse angle and λ  is an integer, then the number of value(s) of λ is/are

Let a¯=λi^−3j^+5k^ and b¯=2λi^−λj^−k^ The angle between the vector a¯ and b¯ is an obtuse angle then a¯⋅b¯<0⇒(λi^−3j^+5k^)⋅(2λi^−λj^−k^)<0⇒2λ2+3λ−5<0⇒(2λ+5)(λ−1)<0⇒λ∈−52,1 Integer values of λ are −2,−1,0 Hence, the number of values of λ is 3Therefore, the correct answer is(1).