Question

Va rog urgent (a, b, c) dau Coroana!!!!!! ​

Answer 1

Răspuns:

a)-13√2 b)4,6√3 c)-5√5

Explicație pas cu pas:

a) √18-3√32+2√8-√72=√(9×2)-3√(16×2)+2√(4×2)-√(36×2)=

=3×√2-3×4×√2+2×√2-6×√2=3√2-12√2+2√2-6√2= -13√2

b) 0,4√12-0,9√27+1,3√75=0,4×√(4×3)-0,9×√(9×3)+1,3×√(25×3)=

=0,4×2×√3-0,9×3×√3+1,3×5×√3=0,8√3-2,7√3+6,5×√3=

=(0,8-2,7+6,5)×√3=(7,3-2,7)×√3=4,6√3

c) -2√80+√320 -4√20+√45= -2×√(16×5)+√(64×5)-4×√(4×5)+√(9×5)=

=-2×4×√5+8×√5-4×2×√5+3×√5=-8√5+8√5-8√5+3√5=-5√5