The Total solution for NCERT class 6-12
Answer - 31 : -
Answer - 32 : -
Answer - 33 : -
3 is a zero of f(x) = 2x2 +x + kIt will satisfy the polynomialf(x) = 0 ⇒ f(3) =0Now 2x2 + x + k = 0=> 2 (3)2 + 3 + k = 0=> 18 + 3 + k = 0=> 21 + k = 0=> k = -21
Answer - 34 : -
-3 is a zero of polynomial f(x) = x2 +11x + kIt will satisfy the polynomialf (x) = 0 => f(-3) = 0Now x2 + 11x + k = 0=> (-3)2+ 11 x (-3) + k = 0⇒ 9 – 33+ k = 0⇒ -24 +k = 0⇒ k = 24
Answer - 35 : -
-2 is a zero of the polynomialf(x) = 3x2 + 4x + 2kf(-2) = 0=> 3 (-2)2 + 4 (-2) + 2k = 0=> 12 – 8 + 2k = 0=> 4 + 2k = 0=> 2k = -4=> k = -2
Answer - 36 : -
In a quadratic polynomial f(x) its degree is 2 and it can befactorised in to two distinct linear factors.f(x) has two distinct zeros
Answer - 37 : -
Answer - 38 : - A quadratic polynomial f(x) is not factorised into linear factors It has no real zeros It is true
Answer - 39 : -
Answer - 40 : -
The graph of quadratic polynomial ax2 +bx + c cuts positive direction of y-axis Then sign of constant term c will bealso positive.